Method and forming tool for hot-forming a flat thermoplastic laminate

ABSTRACT

A flat laminate element made of thermoplastic is hot-formed in a two-stage method. In a first stage, the flat laminate which includes film(s) and/or panels(n) is placed on a flat frame-shaped pallet and is heated to a forming temperature in a heating zone between two flat heat screens in a contactless manner. The edge zone of the hot flat laminate element lies on the pallet such that the laminate piece cannot be clamped in a first laminate direction but rather can be slide on the pallet in this direction. Two non-flat rigid contours which are identical or largely identical act on two opposing parallel laminate edge sections uniaxially and perpendicularly to the laminate plane and only in the first laminate direction, i.e. monodirectionally, and shape the entire heated laminate element into a monodirectionally molded blank.

RELATED APPLICATIONS

This application is a continuation of international applicationPCT/EP2017/000367 filed on Mar. 24, 2017, claiming priority from GermanPatent Application DE10 2016 004 047.5 filed on Apr. 4, 2016, both ofwhich are incorporated in their entirety by this reference.

FIELD OF THE INVENTION

The instant invention relates to a method for hot forming a flatlaminate made from a thermoplastic synthetic material. This methodfacilitates producing 3D-molded components from foils or plates.Furthermore this method can be used for coating a 3D-carrier elementwith a laminate. The invention also relates to the products producedaccording to the method. Furthermore, the invention relates to a formingtool for performing the method.

The “3D-formed element” and the “3D-carrier element” designates a solidcomponent or an object or body with a three dimensional surface contouror configuration or geometry. The laminate can be configured with onelayer or multiple layers. A typical laminate includes at least a foiland/or plate respectively configured from thermoplastic syntheticmaterial, which can be, for example, polycarbonate PC,poly(meth)acrylate (PMMA), polyester (ME), polyamide (PA),polyarylsulfones (PSU) or polyvinylchloride (PVC).

A foil or plate of this type can be imprinted metalized or coatedotherwise, at least in portions of one or plural surfaces which providesa decorative appearance to the 3D-molded component or the coated3D-carrier element and increases its utility. A multilayer laminate caninclude an additional laminate in addition to at least one foil and/orplate respectively made from a thermoplastic material.

Products produced according to the method according to the invention arefor example used as interior furnishings of motor vehicles, thus, e.g.,the dashboard or parts thereof; furthermore, applications and othercomponents of furniture and housings and/or components of otherdecorative high value consumer products. 3D-molded components made fromfoil can be back injection molded with another synthetic material.Methods like insert molding, compression molding and other methods ofthis type provide multilayer, optionally thin wall molded componentswhere a design is arranged within the mass of the molded component andthus protected against abrasion.

Transparent synthetic material plates can be used, for example, forcambered window panes for vehicles including motor vehicles, ships(portholes) and for aircraft, visors for crash helmets, windscreens formotor vehicles, clear covers and fairings for machines and other stable,clear, large surface components with a configuration or camber thatprotrudes from an original plane.

In more detail the invention relates to a method of the preamble toclaim 1.

BACKGROUND OF THE INVENTION

The documents U.S. Pat. No. 5,108,350 A, EP 0 371 425 B1 or DE 38 40 542C1 disclose a method for producing a deep drawn synthetic materialmolded component wherein cold stretchable foil material at an operatingtemperature below a softening temperature of the foil material isindirectly and directly loaded by a liquid pressure medium at a pressuremedium pressure greater than 20 bar and isostatically molded within atime period of less than 5 seconds. Advantageously a pressure mediumpressure between 50 and 300 bar can be used. A foil that is providedwith a color imprint can be advantageously formed at an operating tempbetween 80° and 130° C. For forming the initially flat foil is appliedto a tool by a fluid pressure medium pressed into contact and moldedwherein the tool is arranged in a forming station. After the highpressure forming an additional advantageously transparent syntheticresin can be injection molded onto the molded component or deep drawncomp thus obtained. This yields form stable self-supported 3D-formedelements made from thermoplastic synthetic material. This method isdesignated in the art as “high pressure shaping” or “high pressuremolding” of synthetic foils or as maximum pressure forming or coldforming according to the high pressure forming (HPF) or after theinventor as Niebling method.

High pressure forming of plates with thicknesses of 2-18 mm made fromthermoplastic synthetic material under HPF conditions is disclosed inthe document WO 2015 025285 82 and in the document EP 2 958 733 B1.

Devices for performing the HPF method are described, e.g. in thedocuments DE 41 13 568 C1 or DE 10 2008 050 564 A1.

The HPF method is characterized by an abrupt forming of the syntheticmaterial foil sing a fluid pressure medium under a pressure mediumpressure greater than 20 bar. The resistance of the plastic foil thathas not been completely softened yet against the forming is overcome bythe high pressure medium pressure. This is the essential difference overthermoforming as described, e.g., in the textbook “Thermoformen in derPraxis” by Peter Schwarzmann, second edition, Carl Hanser Publishing,Munich 2008. When performing thermoforming a resistance of the syntheticmaterial foil against the forming is reduced in that the forming of thefoil or of the semi-finished product is performed at or above asoftening temperature of the foil or of the semi-finished material. Thesoftened plastic to almost melt liquid foil only poses very littleresistance against the forming so that the forming can be performedunder vacuum with a pressure differential of 1 bar over ambient, or bycompressed air forming under a molder pressure of up to approximately7.5 bar. Since the compressed air forming is performed at a highermolding pressure than vacuum forming, the compressed air forming istypically performed at a lower forming temperature than the vacuumforming. When performing vacuum forming the foil or the semi-finishedproduct has to be even more plastic even softer and deformable even moreeasily because a smaller effective molding pressure of approximately 1bar is provided.

In this book it is stated regarding “Thermoformen au Plattenmaschinenen”on page 105: “The thermoforming method can be broken down into steps,the preforming or pre-stretching and the final forming. Since the wallthickness distribution that is achieved solely by forming with vacuum orcompressed air does not suffice, preforming has to be performed. It is agoal of the preforming to achieve a contour which resembles the contourof the finished component as closely as possible. The crisp forming isachieved in the finishing step. In most cases the preforming is moreimportant for wall thickness distribution than the finished forming. Thepreforming always includes a pre-stretching and can be performed indifferent ways, e.g., by

-   -   mechanical pre-stretching by the forming tool itself;    -   mechanical pre-stretching by an auxiliary plunger;    -   pneumatic pre-stretching by pre-blowing or vacuum pre-pulling;        and    -   a combination of mechanical or pneumatic pre-stretching.

A corresponding “Negative Forming with Pre-stretching Plunger” is shownon page 114; a bubble is generated by pre-blowing into which apre-stretching plunger penetrates. A corresponding “Positive-negativeforming” is illustrated on page 116; “the preforming is performed bypre-blowing and the formed bubble is subsequently pushed over into apreformed blank by a mechanical plunger, this means into a contour whichis sim to the contour of the finished component; thereafter the finishedforming is performed under vacuum.”

There is no recitation of different or various fixed forming tools ornon-flat contours which generate molded components with differentcontours during a forming method.

An improvement of high pressure forming of synthetic material foilsunder HPF conditions relates to coating a single layer or multilayerinitially flat laminate, like, e.g., a synthetic material foil underhigh pressure forming conditions to a 3D-carrier element. A method ofthis generic type is known from the document DE 10 2010 021 892 B4.

The Document DE 101 53 035 B4 relates to a clamping frame. The clampingframe supports mats that are to be molded three dimensionally inparticular glass fiber reinforced mats, at a pressing tool which has aforming non-flat contour at a lower tool and a congruent forming,non-flat contour at an upper tool. In order to perform the threedimensional forming an initially flat mat is introduced between thecontours and the upper tool is applied to the lower tool wherein the matis deformed according to the forming contours. The clamping frame isformed by four upper bars at the upper tool and by four lower bars thatare arranged parallel to each other at an offset at the lower tool. Eachbar is made from an elastic material, e.g., spring steel, and providedwith magnets with opposite polarity. After introducing the flat matbetween the upper and lower bars pairs of bars that fit together arejoined and kept together by a magnetic force. Each pair of bars can beadjusted by lifting devices towards the lower tool with differentspacing so that a coarse shaping of the originally flat mat is performedat the forming contour at the lower tool.

The Document DE 10 2010 041 179 A1 relates to a method for producing ablank from a fiber material. Thus a fiber mat is pulled over a clampingframe that includes a first clamping frame element and a second clampingframe element with the fiber mat clamped in between. The clamping frameis arranged between an upper tool and a lower tool of a pressing tool.Closing the pressing tool pulls the fiber mat into a mold cavity of thepressing tool. In particular, the fiber mat is clamped between contactsurf of the clamping frame elements which are not flat. The clampingforce by which the uneven clamping frame elements clamp the fiber mat isadjusted so that the fiber mat can slide towards the pressing tool whenthe pressing tool is closed. This is done with the intention to preventa wrinkling of the blank as far as possible.

The known HPF method is a deep drawing method. Deep drawing, expandingand stretching provide additional surfaces at the 3D-molded comp whichare not provided at the originally flat laminate. The surface increaserequires material movements which in turn cause layer thicknessvariations. Quite frequently additional tension surfaces have to beprovided at the flat layer material wherein laminate material canmigrate to the 3D molded component in order to form the flat laminate.The remaining tension surface residuals have to be removed thereafter,which increases material consumption without providing additionalutility. A substantial expansion and stretching damages thin metalconductor paths that are applied to the flat layer material in order tofacilitate a conduction of current and/or voltage at the 3D moldedcomponent. These and additional findings can be summarized as follows:Deep drawing creates deep drawing stress, which causes damages and otherdisadvantages at the deep drawn product.

There have been various proposals to reduce or eliminate the deepdrawing stress.

The document WO 2011/083013 A2 proposes to reduce the deep drawingstress during deep drawing under HPF conditions in that heating a flatfoil element in a heating zone heats one or plural foil portion(s) ofthe foil element which were heated more before the forming so that theseportions are stretched more during the forming (outer portion) and tostretch the portions which were heated less before the forming arestretched less or not at all during the forming (utilized portion),wherein a temperature difference between the utilized portion and theouter portion shall be 10° to 50° C. The different heating betweenutilized portion and outer portion shall be performed by an appropriateintroduction of apertures between the foil and heat radiators in theheating zone. The outer portion is used for tension surfaces and tensionsurface leftovers that remain after the forming have to be removed whichincreases material consumption.

Also the document DE 10 2009 048 334 A1 defines a utilized portion andan external scrap portion at the foil piece that is to be formed underHPF conditions. In the external portion one or plural cuts shall beprovided that envelope the utilized portion and which cut the foilcompletely adjacent to the portion to be formed. During the isostaticforming of the flat foil element under HPF conditions these cuts areexpanded into gaps that are several millimeters wide. Instead of formingnew surfaces by expanding the foil in the utilized portion of the foilelement, new surfaces are formed outside of the utilized portion bywidening the cuts into pronounced gaps; migrating foil material that hasto be transported is replaced by air. The expansion stress of the foilsection is the utilized portion of the foil piece shall be significantlyreduced.

BRIEF SUMMARY OF THE INVENTION

Thus it is an object of the instant invention to significantly reducedeep drawing stress compared to convention classic HPF methods duringhot forming of flat laminate materials made from a thermoplastic synmaterial under HPF condition, in particular when a significant singleaxis forming is performed orthogonal to the laminate material plane.

According to the method according to the invention, 3D molded componentsshall be produced from the originally flat laminate that is made from athermoplastic synthetic material. Furthermore, a predetermined 3Dcarrier element shall be coated according to the method with anoriginally flat laminate that is made from a thermoplastic syntheticmaterial under HPF conditions, wherein deep drawing stress is reduced.

Furthermore, a forming tool shall be provided for performing the methodaccording to the invention.

A first object of the instant invent relates to a method hot forming alaminate made from a thermoplastic synthetic material to produce a 3Dformed element or to produce a 3D carrier element that is coated with alaminate material.

Improving upon a method for hot forming a flat laminate element madefrom a thermoplastic synthetic material into a 3-D formed element or forcoating a 3-D carrier element, wherein the flat laminate element isapplied to a frame of a frame shaped pallet with a rim zone of thelaminate element and heated to a pre-determined temperature, and a formsurface of the heated laminate element is loaded within the rim zonewith a fluid pressure medium, in particular compressed air, with apressure medium pressure of 20 bar to 300 bar and formed under constantpressure into the 3-D formed element within a time frame of less than 5seconds or laminated onto the 3-D carrier element, (isostatic highpressure forming) the solution is characterized in that the flatlaminate element is arranged with the rim zone on the frame so thatportions of the rim zone of the heated flat laminate element areconfigured to slide on the frame in a first laminate material direction;and initially two predetermined identical or substantially identical nonflat contours impact two laminate material rim portions that arearranged parallel and with an offset from each other and opposite toeach other, wherein the non-flat contours impact along an axisorthogonal to a laminate plane and form an entire heated laminateelement only in this first laminate material direction, thus monodirectionally into a hot mono directionally formed blank; and whereinisostatic high pressure forming is subsequently performed upon the monodirectionally formed blank.

As long as two “substantially identical” contours of the flat laminatepiece are formed into a mono directionally molded blank this means thatthe flat laminate piece is formed without stretching or with littlestretching. Forming with low stretching is considered a forming whichgenerates a surface increase of less than 4% at the original surface.

A forming method where a forming is only performed in a laminatedirection in which the laminate is not clamped for a single axis formingof the flat laminate to the laminate plane of a flat laminateperpendicular to the laminate plane wherein however no simultaneousforming is performed in the orthogonal laminate direction issubsequently designated as “single axis mono direction forming” ortypically abbreviated as “mono directional forming.” A flat laminate canonly be formed in one axis orthogonal to the laminate plane, so thatreciting the single axis forming orthogonal to the laminate plane is notmandatory. An essential feature of the instant invention is the monodirectional forming of the flat laminate.

With reference to FIG. 1 a mono directional forming and the obtained“mono directionally formed blank” is described further with the featuresof claim 2.

For example a rectangular flat laminate piece E is processed which haslonger sides F in a cartesian coordinate system parallel to the X-axisand shorter sides G parallel to the Y-axis. At this flat laminate pieceE an imaginary grid is arranged with parallel straight lines “F1-Fn”that have even spacing from each other which are oriented parallel tothe sides “F” and parallel straight lines “G1-GN” that have uniformspacing relative to each other and that are oriented parallel to thesides G. An impact of 2 offset, fixed, identical non-flat contours, thuse.g. a contour that includes a partial circle with a radius r=30 mm. Inone axis orthogonal to the X, Y plane, thus in “Z” direction and only inthe Z direction, thus mono directionally causes a forming of the flatlaminate element E into a mono directionally formed blank V which onlyhas an additional extension in the Z direction wherein the chord thatwas 50 mm long originally has become a circular arc K with a length of63 mm so that the mono directionally formed blank V has a length in Xdirection that is 30 mm less, than the original flat laminate piece Eand therefore portions of this originally flat laminate piece have to beable to slide on a surface that supports this laminate piece. A “monodirectional forming” is characterized in that and interpreted so thatthe original straight lines F1-Fn have become cambered lines H1-Hn atthe mono directionally formed blank V whereas the original straightlines G1-Gn have been maintained as straight lines G1-Gn with theiroriginal lengths. Therefore the mono directional forming of the flatlaminate piece E in X-direction has not caused any forming of the flatlaminate piece E and displacement of laminate portions in the orthogonalY-direction.

If the mono directional forming is performed by two offset fixedsubstantially identical contours a small amount of stretching. A lowstretch forming is considered a forming which causes an increase of lessthan 4% at the original surface.

The instant invention is based on the following idea.

The flat laminate piece has to be heated before forming. A heating ofthis type is performed simply and quickly in a heating zone, which isformed between 2 heating fields that essentially have identicalsurfaces, are offset from each other and essentially horizontallyoriented and which are provided with heat radiators that generate IRradiation. For example infrared flat radiators or ceramic radiators canbe used for this purpose. In a heating zone of this type a flat laminatepiece can be heated in a simple, quick and controlled manner. Acontrolled heating of a cambered or otherwise three dimensionally shapedlaminate element would be much more complex consequently the heatingprovided according to the invention shall be performed upon a flatlaminate piece which rests on a flat frame of a carrier, in case of theinstant invention on a flat frame of a frame shaped pallet.

Depending on a shape of the 3 D formed element or of the 3 D carrierelement to be coated a larger or smaller stretching of the flat laminateelement will occur for a one stage forming of the hot, flat laminateelement into a 3D formed element of this type or forming the hot flatlaminate element onto a 3D carrier element. It was found by theinventors that the hot flat laminate element can be formed into a 3dimensional blank by a forming that occurs only in one laminatedirection, thus a mono directional no stretch or low stretch formingwherein a shape of the three dimensional blank is already very close toa shape of the final product. Molding the flat laminate element into themono directionally formed blank is performed through an impact of 2contours that are offset from each other, fixed, identical orsubstantially identical and non-flat upon 2 parallel offset oppositeedge section of the laminate element which is not clamped at its tworemote ends in a first laminate direction that is perpendicular to theforming direction and which can therefore slide on its support base.

Thus, it is a core idea of the invention to replace the flat contactsurface at a flat pallet from that is required for heating the flatlaminate material during the process with a non-flat contact surfacecontour at the contact surface of a clamping frame or of a spring frameor of a frame structure that is supported and attached at the clampingframe or spring frame and to provide a transfer of the initially flatlaminate element from the flat pallet frame to the non-flat contactsurface contour. According to the inventors such clamping frames orspring frames or a structure on such clamping frame or spring frame forhot forming flat laminate laminates from thermoplastic syntheticmaterial wherein the clamping or spring frames are respectively providedwith 2 parallel offset opposite non-flat contact surface sections whichimpact 2 parallel offset opposite laminate edge section and thus formthe entire laminate piece mono directionally are no known in the art.

Minor stretching can thus occur at the mono directionally formed blankwhen the shaping mold is raised further relative to the blank that isclamped between the seal surface contour at the upper forming tool halfand the congruent contact surface contour at the lower forming tool halfand thus penetrates through the blank shape in order to perform atypically minor orienting “mechanical” positive forming at the clampedblank. In this case a “mechanical” forming is performed by an impact ofa plunger upon a blank that is previously generated without stretchingor with little stretching. This subsequent “mechanical forming” is notamong the measures to produce the blank according to the invention.

The bland thus obtained is subsequently subjected to isostatic highpressure forming under HPF conditions. Since the shape of the blank isalready substantially or mostly adapted to the three dimensional shapeof the 3D formed element to be produced or the 3D carrier element to becoated the subsequent high pressure forming creates a lower stretchingof the laminate element compared to direct single stage forming of theflat base material into the three dimensional end product.

Preventing or reducing the stretching of the hot flat laminate duringisostatic high pressure forming under HPF conditions has substantialadvantages. Stretching causes layer thickness unevenness and expansionswhich damages surface structures which influence optical and/or hapticperceptions and cause distortions to applied printed images, decorativepatterns and designs.

Less stretching avoids these damages and expands applications of the HPFmethod. According to the invention 3D shaped elements were produce ablewhose shape includes larger distances from a plane of a startingmaterial compared to what was possible according to the HPF method. Forexample cambered or spherical 3D shaped elements can be produced by themethod according to the invention which are approximately 1 meter longand whose apex line has a maximum distance from the starting plane of10-15 cm.

Less stretching facilitates applying narrow or thin electricallyconductive paths onto the flat laminate element wherein the conductivepaths survive mono directional shaping into the mono directionallyshaped blank and its shaping under HPF conditions into the 3D shapedelement without getting damaged so that light emitting diodes LEDs atthe 3D shaped element can be provided with voltage and current by theconductive paths.

Less stretching reduces a requirement for tension surfaces whoseresiduals would become scrap which yields material savings and theshaping surfaces at an existing shaping tool can be utilized better.

Less stretching requires less heating of the flat starting materialwhich in turn improves imaging crispness of contours and imagingprecision of applied printed images, decorative patterns and designs.Another object of the instant invention relates to a forming tool forperforming the method.

Another aspect of the invention relates to a forming tool for performingthe method according to the invention.

The document DE 10 2008 050 564 A1 discloses a forming tool for highpressure forming a single layer or multi-layer laminate elementcomprising an upper forming tool half which forms a pressure bell

-   -   into which a fluid pressure medium, in particular compressed air        is introducible at a fluid medium pressure of 20 bar to 300 bar,        and    -   which includes a circumferential sealing surface (85) in which a        circumferential groove is recessed into which a sealing device        is inserted; and

comprising a lower forming tool half,

-   -   which includes a base plate on which a substructure is supported        at which a mold with mold contours or a carrier element that is        to be laminated and which is provided with 3-D carrier element        contours is attached, at which contours the laminate that is        loaded with the fluid pressure medium is formed; and    -   the substructure is enveloped by a tension frame supported at        the base plate or by a spring frame that is supported on        compression springs at the base plate wherein the hot laminate        element to be formed is applicable to the tension frame or the        spring frame; and

the lower forming tool half can assume a release position that is remotefrom the upper forming tool half and a closing position that is adjacentto the upper forming tool half; wherein

-   -   in this release position the transport frame with the frame        shaped pallet and the hot laminate element placed thereon is        insertable between the two forming tool halves and assumes a        position in which the tension spring or the spring frame assumes        an arrangement within and below the recess at the frame shaped        pallet;    -   in the closing position the hot laminate element maintains a        small distance from the sealing surface at the pressure bell and        is applicable at this location to the sealing device so that the        pressure bell is sealed pressure tight relative to the laminate        element; and    -   in this arrangement a fluid pressure medium, in particular        compressed air, is introducible at a pressure medium pressure of        20 bar to 300 bar which forms the hot laminate element within a        time period of less than 5 seconds isostatically to the form        contours or to the 3-D carrier element contours. The improvement        of the forming tool according to the invention is characterized        in that    -   the tension frame of the spring frame includes a respective        contact surface section including a non-flat contour at two        parallel offset and opposite frame sections wherein the        respective contact surface sections form a non-flat contact        surface in combination; or    -   the tension frame or the spring frame includes a frame on which        a frame assembly is supported and fixed which includes a        respective contact surface section including a non-flat contour        at two side walls that are parallel offset from each other and        arranged opposite to each other wherein both contact surface        sections form a non-flat contact surface contour;    -   the pressure bell respectively includes a sealing surface        section at pressure bell sections that are arranged in parallel        with an offset from each other and opposite to each other        wherein the respective sealing surface sections include a        non-flat contour which form a non-flat sealing surface contour        in combination, wherein the non-flat sealing surface contour is        configured congruent to the non-flat contact surface contour;        and    -   during lifting of the lower forming tool half for reaching the        closing position of the forming tool the non-flat contact        surface sections reach under two parallel offset and opposing        laminate element rim sections at the tension frame, the spring        frame or the frame assembly and the non-flat contact surface        sections move the laminate element rim sections along and        eventually proximal to the sealing surface including the        non-flat sealing surface contour of the pressure bell so that        the entire hot flat laminate element is formed at the congruent        non-flat contours monoaxial along an axis orthogonal to the        laminate plane and only in the first laminate material direction        thus mono directionally into a blank (W) that is adapted to the        contours and formed mono directionally.

The method according to the invention can be performed by a forming toolthat includes the entirety of the features described supra.

Advantageous embodiments and improvements of the instant invention canbe derived from the dependent claims.

Advantageously it is provided that a stretch free or low stretch formingis performed upon the warm flat laminate element in a first step of themethod according to the invention in order to produce a monodirectionally formed blank.

A stretching increases a surface of the originally flat laminateelement. In the context of the instant invention a “low stretch forming”if a forming which generates a surface increase of less than 4% at theoriginal surface, advantageously of less than 2% and particularlyadvantageously less than 1%. With a surface increase of less than 1% nolayer thickness variations can be found in the end product anddistortions of printed images decorative patterns and designs applied tothe laminate element are negligible.

Advantageously it is provided in the method according to the inventionthat the 2 offset fixed, identical or substantially identical non-flatcontours are arranged at a contact surface of 2 parallel, offset andopposite frame sections of a clamping frame or spring frame or at acontact surface of 2 parallel, offset and opposite side walls of a framestructure which is supported and attached on a frame of the clampingframe or of the spring frame and this clamping frame or spring frame islifted relative to the frame shaped pallet on which the hot and flatlaminate element rests.

As matter of principle also “negative” mono directional shipping of theflat laminate element can be caused by a contact of non-flat contourswhich are arranged at a pressure bell when the pressure bell is loweredwith respect to the laminate element that is held in place. This method,however, causes a high level of mechanical complexity.

The two non-flat contours that are advantageously arranged at contactsurface of the clamping frame or of the spring frame or of the frameshaped super structure are configured identical or substantiallyidentical. “Substantially identical” means that a contact of the flatlaminate element at these contours and a subsequent mono directionalshaping at these contours can be performed substantially withoutwrinkling or stretching or essentially without stretching.

“Essentially without stretching” means with little stretching, a “lowstretch forming” is defined as forming which creates a surface areaincrease of less than 4%, advantageously less than 2% and particularlyadvantageously less than 1% at the original surface.

The non-flat contours which are advantageously arranged at a contactsurface of the tension frame or of the spring frame or of the frameshaped super structure can be without being limited thereto; e.g.,roof-shaped evenly or unevenly curved or cambered or provided with anapex point or configured wave shaped or upward sloped in severalincrements. “Uniformly curved” can indicate a circular arc or anelliptic arc, “non-uniformly curved” can be a moderately curved orcambered boundary line which has a single apex point and whichtransitions at its ends into downward sloped branches which subsequentlyform patterns for the side surfaces.

The formed surface at the flat laminate element that is provided for anisostatic high pressure forming under HPF conditions is not reduced orimpaired by the preceding mono directional forming. The monodirectionally formed blank has the same formed surface area as theoriginal flat laminate element.

Advantageously the method according to the invention for hot forming aflat laminate element made from a thermoplastic synthetic material canbe performed by the subsequent devices and measures.

In an arrangement including a loading station and unloading station, aforming station, a heating station and optionally a temperaturemeasuring station a rectangular transport frame is provided in theloading and unloading station wherein the transport frame is movablealong its two longitudinal sides on a straight rail which runs throughan entire arrangement;

a frame shaped pallet is placed on the transport frame wherein a frameof the pallet envelops a recess;

the flat laminate element to be formed is placed in a defined positionon the frame shaped pallet, wherein merely a rim zone of the laminateelement contacts the frame of the frame shaped pallet;

the transport frame with the frame shaped pallet and the flat laminateelement is moved along the two rails from the loading and unloadingstation through the forming station into the heating station wherein theflat laminate element is heated touch free to a predeterminedtemperature;

subsequently the transport frame is moved together with the frame shapedpallet and the hot flat laminate element along the two rails from theheating station back into the forming station where the transport framesupported at the two rails is arranged in a defined manner relative to aforming tool, comprising:

-   -   an upper forming tool half which forms a pressure bell into        which a fluid pressure medium, in particular compressed air is        introducible under a high pressure medium pressure and which        includes a circumferential sealing surface in which a        circumferential groove is recessed into which a sealing device        is inserted;    -   a lower forming tool half including a base plate on which a base        is supported at which a mold including mold contours, or a 3-D        carrier element is attached that is to be laminated and which        includes carrier element contours;    -   the base is enveloped by a tension frame supported at the base        plate or a spring frame supported by compression springs at the        base plate, wherein the hot flat laminate element to be formed        is place able onto the spring frame;    -   the lower forming tool half is configured to move into a release        position that is remote from the upper forming tool half and a        closing position that is adjacent to the upper forming tool        half;    -   in the release position the transport frame with the frame        shaped pallet and with the hot flat laminate element is        insertable between the two forming tool halves and assumes a        position in which the tension frame or the spring frame is        arranged within and below the recess at the frame shaped pallet;    -   in the closing position the hot flat laminate element maintains        a small distance from the sealing surface at the pressure bell        and is applicable to the seal device at this location, wherein        the pressure bell is sealed pressure tight relative to the        laminate element; and

in this arrangement a fluid pressure medium, in particular compressedair, is introduced into the pressure bell at a pressure medium pressureof 20 bar to 300 bar,

wherein the pressure medium forms the hot laminate element within a timeperiod of less than 5 seconds isostatically to the mold contours or tothe 3-D carrier element contours;

The method is improved according to the invention in that

-   -   the flat laminate element contacts the frame of the frame shaped        pallet with the rim zone so that portions of the rim zone of the        hot flat laminate element are configured to slide on the frame        in the first laminate element direction;    -   the tension frame or the spring frame includes a respective        contact surface section at two frame sections that are arranged        parallel to each other offset from each other and opposite to        each other wherein the contact surface section has a non-flat        contour, wherein the two respective contact surface sections        together form a non-flat contact surface contour; or    -   the tension frame or the spring frame includes a frame on which        a frame assembly is supported and attached which frame assembly        includes a contact surface section with a non-flat contour at        two side walls that are parallel to each other, offset from each        other and arranged opposite to each other wherein both contact        surface sections in combination form a non-flat contact surface        contour;    -   the pressure bell respectively includes a sealing surface        section at pressure bell sections that are arranged in parallel        with an offset from each other and opposite to each other        wherein the respective sealing surface sections include a        non-flat contour which form a non-flat sealing surface contour        in combination, wherein the non-flat sealing surface contour is        configured congruent to the non-flat contact surface contour;        and    -   during lifting of the lower forming tool half for reaching the        closing position of the forming tool the non-flat contact        surface sections reach under two parallel offset and opposing        laminate element rim sections at the tension frame, the spring        frame or the frame assembly and the non-flat contact surface        sections move the laminate element rim sections along and        eventually proximal to the sealing surface including the        non-flat sealing surface contour of the pressure bell so that        the entire hot flat laminate element 3 is formed at the        congruent non-flat contours monoaxial along an axis orthogonal        to the laminate plane and only in the first laminate material        direction thus mono directionally into a blank that is adapted        to the contours and formed mono directionally.

Thereafter the fluid pressure medium is introduced into the pressurebell under a high pressure medium pressure which forms the intermediaryhot blank isostatic ally according to the mold contours or the carrierelement contours. Thereafter the pressure bell is ventilated and theforming tool is opened. In particular in case of form element contoursor 3D carrier element contours with a pronounced geometry the upperforming tool half can be subsequently raised by certain distance inorder to increase an intermediary space between the sealing surface andthe transport frame, so that the transport frame with the frame shapedpallet on which the formed 3D formed element or the coated 3D carrierelement is arranged can move out of the forming station into theplacement and extraction station.

This method facilitates producing 3D formed elements which have a ratherlarge extension relative to a plane of the originally flat laminatewhile still being substantially free from layer thickness variations.Furthermore, 3D carrier elements that are coated with a laminate can beproduced according to the method which have a void free high qualitysurface that is optically perfect.

It is furthermore provided that the clamping frame or the spring framehas a frame with a boundary zone and the boundary zone reaches under thebottom side of the frame shaped pallet at its inner circumference duringthe lifting movement of the lower forming tool half, lifts the palletwith the laminate piece arranged thereon by some distance and thusseparates it from the transport frame that is held in place. Thispreform blank still rests on the frame of the frame shaped pallet withits flat end sections that extend in the first laminate direction andthe frame forms a device to move the flat end sections towards the flatsections of the sealing surface and to seal them pressure tight relativeto the sealing surface. Also the product formed according to isostatichigh pressure forming remains on this frame with its flat end sections.The frame shaped pallet which supports the product is lowered onto thetransport frame that is held in place and the transport frame togetherwith the pallet and the product arranged thereon can be moved from theforming station into the loading and unloading station.

In case of 3D formed elements being manufactured or coated 3D carrierelements being manufactured that respectively have a pronounced geometrywhich substantially differs from the original laminate plane it can beadvantageously additionally provided that after completion of isostatichigh pressure forming and ventilating the pressure bell the frame shapedpallet on which the formed element or the laminated 3-D carrier elementis arranged is lowerable relative to the upper forming tool half andplace able onto the transport frame that is fixed in place; and

thereafter the upper forming tool half is liftable by a predeterminedamount in order to render the transport frame with the 3-D formedelement placed thereon or the coated 3-D carrier element removablewithout interference from the forming zone and movable into the loadingand unloading station.

Thus, also products with a pronounced geometry can be retrieved from aforming tool that is in its extended retrieval position.

Depending on a size of the surface to be formed at the laminate elementvarious seal devices can be provided in the groove at the sealingsurface of the pressure bell. In case of a molded surface is less than800 cm² at the laminate element to be hot formed no larger camberedchanges will typically occur at the cavity of the pressure bell whenloaded with the high pressure fluid so that a typical O-ring made froman elastic circular thread with a diameter of approximately 3 mm to 6 mmwill suffice. In order to implement a mold surface of at least 800 cm²the press and the pressure bell have to be maximum pressure mediumpressure of 300 BAR at least for a mold closing force of 2.4 MegaNewton. The press and the pressure bell yield under these tremendousforces and certain bending and warping can occur which would drive acircular thread that is more than 100 cm long out of its groove in orderto still assure a pressure tight sealing of the pressure bell a moreeffective pressure medium has to be used under these more severeconditions.

In this case the sealing device at the sealing surface of the pressurebell is a strand shaped profile seal which includes a body that isinserted into a groove at a sealing surface, wherein an elastic seal lipprotrudes from the body which seal lip includes an outer seal lip flankand an inner seal lip flank;

in a closing position of the forming tool the contact surface maintainsa distance at the lower forming tool half from the seal surface at theupper forming tool half, wherein the distance has a dimension:

[thickness of the laminate element to be formed plus (100 μm to 1200μm)]

so that a gap between the non-flat contact surface and the non-flat sealsurface is formed; and

the pressure fluid flowing under a high pressure fluid pressure into thepressure bell impacts an inner seal lip flank and deforms the elasticseal lip so that the seal lip bridges a gap and seals the rim zone atthe mono directionally formed blank pressure tight relative to the sealsurface at the pressure bell.

This distance assures that the laminate element can slide in the gapbetween the strand shaped profile seal at the sealing surface of theupper forming tool half and the lower forming tool half for a monodirectional forming on the non-flat contours of the contact surface.Furthermore the heavy massive components of the 2 forming tool halves donot contact each other in the closing position either so that damagingor comparing these components can be safely avoided.

The method according to the invention performs hot forming a laminatemade from a thermoplastic synthetic material. Suitable syntheticmaterials are advantageously in particular:

-   -   polycarbonate (PC) or copolycarbonate based on diphenols in        particular also based on bisphenol A and modified bisphenol        compounds;    -   poly- or copolyacrylate;    -   poly or copolymethacrylate, in particular polymethylmethacrylate        or poly (meth) acrylate (PMMA);    -   poly or copolymers with styrol, thus in particular also impact        resistant polystyrol, polystyrolacrylnitril (SAN) and        acrylnitril-butadien-styrol-terpolymers (ABS);    -   thermoplastic polyurethanes (TPU) as a binder in multi-layer        arrangements;    -   polysulfones, in particular polyphenylsulfones and        polyarylsulfones (PSU);    -   polyester (PE), thus in particular poly or copolycondensates of        terephthal acid including poly or copolyethylenterephthalate        [PET or CoPET, glycol-modified PET (PETG)], and poly- or        copolybutylenterephthalate (PBT or CpPBT);    -   polyamide (PA);    -   polypropylene (PP);    -   polyvinylchloride (PVC); and    -   mixes or blends from the preceding materials.

These synthetic materials are typically used in a transparent form.

The laminate according to the invention can be provided as a one layersynthetic material foil or as a multi-layer composite including at leasttwo synthetic material foils wherein each synthetic material foil has alayer thickness of 50 μm to 1000 μm, in particular a layer thickness of200 μm to 750 μm.

The laminate according to the invention can include a one layersynthetic material plate which has a layer thickness of 1000 μm to10,000 μm, in particular a layer thickness of 3000 μm to 10,000 μm or isprovided as a multi-layer composite including one or plural syntheticmaterial plates and is optionally used together with one or pluralsynthetic material foils, wherein a total layer thickness of thecomposite does not exceed 12,000 μm.

The recited laminates are subsequently abbreviated as single layer ormultilayer laminates.

The single layer or multilayer laminates can be placed one layer ormulti-layer laminates are used which are at least partially imprinted ormetalized on one surface or on both surfaces and/or which are coated inanother manner or in case of a multi-layer laminate material an imprintor metallization or other coating can also be provided as a sandwichbetween two layers from transparent plastic materials. An imprintmetallization or other coating delivers an attractive design orattractive decorative pattern.

According to the invention the laminate made from a thermoplasticsynthetic material is heated by radiation heating before forming touchfree so that at least one side of an entire molding surface or a majorportion of the molding surface of the laminate element to be formed hasa surface temperature in a range of [VST (=VICAT softening temperature)B50 (° C.) of the synthetic material−20° C.] up to [VST B50 (° C.) ofthe plastic material plus 23° C.].

These softening temperatures are significantly below the formingtemperatures recommended for thermo forming (c.f. “Thermoformen in derPraxis” by Peter Schwarzmann, second edition, Carl Hanser Verlag, Munich2008, page 40). Which facilitates a better choice of temperaturesensitive coatings and a gentler treatment of these coatings.

In particular for hot forming plates made from glass clear transparentthermoplastic synthetic material the flat laminate element is made froma plate made from a thermoplastic synthetic material with a layerthickness of 3000 μm to 10,000 μm;

the plate is heated in a heating station for a time period between anupper heating field and a lower heating field of a heating devicewherein each heating field includes a heating shield which includes aplurality of individually controllable infrared surface heaters;

the two heating shields are maintained at an average surface temperaturebetween approximately 120° C. above VST 50B (° C.) of the respectivesynthetic material;

and

the plate to be heated that is introduced between the heating shields atambient temperature is maintained between the heating shields for adwelling time that is a function of plate thickness and computed asfollows [(numerical value of plate thickness in mm)×23 seconds+z (sec)]in order to heat the plate to the forming temperature; z has a value of3 to 60.

Self-supported form stable 3D-form elements with a high shapingprecision, with perfect glass clarity and a high level of brilliance anda high level of optical surface quality can be obtained.

The method according to the invention for hot forming a one-layer ormulti-layer laminate from thermoplastic synthetic material is used forproducing a 3D-form element.

Furthermore, this method can be used for producing 3D-carrier elementsthat are coated with a single-layer or a multi-layer laminate. Thelaminate adheres to the 3D-carrier element through a glue.

When producing a 3D-carrier element of this type, it can beadvantageously provided that

a blank made from the laminate that is adapted to the 3-D carrierelement is placed on a transfer foil;

at least a rim zone of this transfer foil is placed on the frame of aframe shaped pallet;

the transfer foil and the laminate material blank are jointly formedinto the mono-directional blank through mono-directional forming;

only the transfer foil thus formed is clamped between the contactsurface at the lower form tool half and the sealing surface at the upperform tool half; and

-   -   when loaded with the high pressure fluid the pressure fluid        impacts the transfer foil and forms the transfer foil together        with the laminate blank wherein the laminate material blank        contacting the transfer foil is applied and laminated to the        3D-carrier element by an adhesive layer.

This method variation facilitates saving a typically rather expensivelayer material, e.g., when structure foils or foils that are providedwith particularly embossed structures (so called “Opto 4D-Foils”) arebeing used.

It is furthermore advantageously provided that the flat laminate elementto be formed is placed on a flat frame shaped pallet whose frame isprovided at its inner circumference with a number of offset inwardextending protrusions and the rim zone of the laminate element is onlyplaced onto the protrusions.

It is furthermore provided that the tension frame or the spring frame orthe side surfaces of the frame assembly supported and fixed on the frameof the spring frame

include a structured outer circumference and a non-flat contact surfacewith inward extending recesses and outward extending bars at the outercircumference;

the outer circumference is adapted to the inner circumference at theframe of the frame shaped pallet so that the clamping frame or thespring frame or the frame assembly is movable at a closed distance fromthe inner circumference of the pallet frame relative to the pallet thatis fixed in place;

the protrusions at the inner circumference of the pallet frame engagerecesses at the outer circumference of the tension frame or of thespring frame or of the frame assembly;

the protruding bars at the outer circumference at the tension frame orthe spring frame or the frame assembly engage the intermediary spacesbetween two respective adjacent protrusions at the pallet frame; and

-   -   when lifting the tension frame or the spring frame or the frame        assembly relative to the pallet that is fixed in place the        protruding bars at the outer circumference of the tension frame        or the spring frame or the frame assembly reach below the rim        sections of the flat laminate element and move them along so        that they deposit the laminate element on the contact surface at        the tension frame or at the spring frame or at the frame        assembly,    -   so that during an additional lifting of the tension frame or of        the spring frame or of the frame shaped super structure with        respect to the fixated upper forming tool half the laminate        element is formed mono directionally into a mono directionally        formed blank between the non-flat contact surface contour (68)        and the congruent non-flat sealing surface contour.

Thus, an essential idea of the invention is implemented where the flatcontact surface at the flat pallet frame is replaced with the non-flatcontact surface contour at the contact surface of the clamping frame ofthe spring frame or of the frame shaped structure. Thus the shapingsurface that is available for shaping is maintained in its entirety atthe flat laminate element.

In this embody of the palette frame it is advantageously provided thatvertically protruding mandrels are attached at the protrusions at theinner circumference of the pallet frame which protrusions engageboreholes or slotted holes that are recessed in the edge zone of thelaminate element so that portions of the edge zone can slide on theframe of the frame-shaped palette. Slotted holes of this type extend inthe first laminate direction and have a sufficient length as a functionof position and arrangement at the laminate element so that the laminateelement can slide on its supporting base surface unimpeded and withoutstretching.

Using the mandrels the predetermined defined arrangement of the laminateelement to be formed can be secured on the one hand side relative to theframe shaped pallet and on the other hand side relative to the formingtool. 3D-formed elements can be obtained whose imprint and/or designcorresponds exactly to a predetermined reference sample.

A flat, single- or multi-layer laminate made from thermoplasticsynthetic material is formed at an elevated predetermined temperature ina two-stage method into a three-dimensional (3D) structure; thus thehot, flat laminate is formed in a first step into a monodirectionallyformed blank which is subsequently formed in a second step underHPF-conditions (=high pressure forming) into a finished 3D-product.

Suitable advantageous thermoplastic synthetic material for the flat basematerial are provided in claim 10. Further details regarding suitablethermoplastic materials are provided in the prior art, e.g., in thedocuments DE 103 27 435 A1, DE 2006 031 315 A1, and EP 2 197 656 B1,thus in paragraph [0023] through [0066]; which are incorporated byreference in order to avoid unnecessary repetition.

For many applications glass clear 3D-form elements or with transparentsections are required. For these applications thermoplastic or opticallytransparent synthetic materials are being used like, e.g., polycarbonate(PC), polymethylmethyacrylate (PMMA), polythylenterephthalate (PET),polyphenylsulfon (PPSU) or polystyrol (PS) and modified materials ofthis type.

Single layer laminates can be foils or plates made from the plasticmaterials. Foils typically have a layer thickness 50 μm to 1000 μm,advantageously 200 μm to 750 μm. Foils with layer thickness of this typeare used quite frequently. For forming 3D-form elements obtained fromthese foils can be back injection molded with additional plasticmaterial in order to obtain form stable, self-supported finishedproducts.

Plates typically have layer thicknesses of 1000 μm to 10,000 μm,advantageously layer thicknesses of 3000 to 8000 μm and particularlyadvantageously layer thicknesses of 4000 to 6000 μm. 3D-formed elementsproduced from such plates are typically not back injection molded withadditional material or otherwise reinforced. Therefore, the platethickness together with the other material properties have to assuremechanical stability, durability, strength and load bearing capabilitywhich are required for the application of the 3D-form element. For manyapplications, e.g., as a cambered plastic pane for motor vehicles orprotective screens for machine enclosures, a plate thickness of 4000 to6000 μm is completely sufficient.

For a multilayer laminate from thermoplastic synthetic material aninterconnection from the preceding synthetic material foils or aninterconnection from the plates and foils recited supra is suitable. Theentire layer thickness of the interconnection shall not exceed 12,000μm. An interconnection made from two or more foils or from two platescan be obtained by co-extrusion or by gluing with a glue. Suitableglues, for example, are thermoplastic polyurethanes (TPU).

A multilayer laminate can include one or plural layers of a materialother than foils and/or plates from a thermoplastic synthetic material.Without being limited thereto, other additional layer materials like,e.g., metal foils, wood veneer foils, on particular burlwood veneers,leather, artificial leather, like, e.g. ALCANTARA (ALCANTARA® is aregistered trademark); furthermore, textile materials like wovenmaterials and knitted materials and laid materials from natural fibersand/or synthetic fibers. Thus, a multitude of decorative effects can beobtained, like, e.g., a high-end piano lacquer look on select tropicalwood veneers like, e.g., burlwood. An interconnection is obtained whichincludes at least one layer of laminate made from a thermoplasticsynthetic material and at least one additional layer made from anotherlaminate material.

Commercially available 3D-formed elements that are produced according tothe invention are typically provided with a graphical, functional and/ordecorative configuration that follows a predetermined layout which istypically applied as a background on a backside of a transparent foil orplate, e.g., as an imprint, metallization and/or other coating, andwhich is visible through the foil layer. Thus, advantageouslytransparent foil and plate materials are being used. A transparent layercan also be provided with a matte surface or a matte lacquer layer inorder to imprint, metallize and/or other coat the opposite surface.Alternatively the decorative effect can be provided by a layer of amultilayer laminate or composite material which is modified orreinforced by one or plural transparent foil layers. For example, thedecorative effect can be provided by a metal foil or a burlwood veneeror by an artificial veneer made from a synthetic material, and thedecorative effect can be modified and reinforced by transparent foils inorder to achieve particular gloss effects, for example, a piano lacqueroptical appearance by foil application as discussed, e.g., in thedocument DE 10 2007 054 579 A1. All of these decorative configurationsincrease the utility of a 3D-form element or 3D-carrier elementconfigured therewith.

Among the elements of a decorative configuration are e.g. numbers,lettering symbols images, pictograms and similar which are applied to asurface of an initially flat foil or plate. This can be done for examplein a multi-stage silk screening method and/or by applying a coatingwhich is applied in plural sequential steps respectively in a liquidlayer. For this alternative application for example offset printingGravure printing or digital printing are suitable. Advantageously animprinting that follows a predetermined lay out is applied by silkscreening. In a multistage silk screening process typically a blackcolor layer is applied initially at which the subsequently visibleelements like numbers, lettering, symbols, images, pictograms andsimilar are recessed in a negative print. In subsequent printing stepsthese recess spots are back filled with color layers in various tones.In order to apply the color layers typically colored lacquers are usedthat are based on polycarbonate or polyester urethane. High temperatureresistant flexible printing colors for imprinting synthetic materialfoils which explicitly tolerate the conditions of the instant HPF-methodand optionally a subsequent insert molding are described e. g. In thedocument DE 198 32 570 C2. The document De 101 51 281 A1 describescolored lacquers which are particularly well adapted for silk screening.PMMA foils and the subsequent forming on the HPF conditions. Liquid silkscreening colors that are particularly well suited for this applicationare sold e.g. by PROELL KG, 91781 Weissenburg, Germany. Highly crosslinked UV hardening silk screening colors sold by Marabu GmbH & Co. KG,71732 Tamm, Germany are also well suited and reduce or prevent thecomplexity that is required for drying and completely removing organicsolvents.

In the context of the instant invention special laminates can be usedand formed. For example the laminate itself can be made from astructured foil or a multilayer laminate can be used whose visible coverlayer is made from a structured foil. Structured foils have a structuredsurface which is formed by protrusions and recesses with respect to aflat nominal surface. Structures of this type can imitate a naturaloriginal, for example the grain of natural leather or the wood grain ata wood surface. Using respective contour data facilitates processing asurface of an embossing roller or the tool surface of a positive ornegative tool. Furthermore synthetic structures can be generatedaccording to predetermined CAD data. By forming or embossing thestructure of the embossing roller or of the embossing tool surface istransferred to a surface of a synthetic material foil. Details forproducing accordingly structured pressing tools can be derived e.g. fromthe document DE 198 55 962 C5 and the literature cited therein. Anexemplary structured foil is sold by Exel GmbH, 83101, Rohrdorf, Germanyunder the model number PMU 4060 UV. This foil is made from a blend madefrom thermos plastic polyurethane and poly meth acrylate and has awaviness of 3 mm at the most. The structured foil can be obtained andused transparent or colored, e.g. colored pitch black.

Other high value embossing foils suitable as layered material are soldby Isosport Verbundbauteile GmbH, 7000, Eisenstadt, Austria with thedesignation “up to 4D foils”. A precisely matched embossing on both sideof a transparent PA 12 foil creates a foil with a unique optical deptheffect (lenticular effect) which has excellent material propertiesincluding excellent scratch resistance and high UV resistance and goodweather resistance which makes these foils also suitable for externalapplications. Due to its high heat resistance embossing foils of thistype can be formed under the conditions according to the invention,wherein a stretch free forming that is possible according to theinvention does not damage or impair the particular embossing structures.

Recently various diffusor foils, reflector foils or light directly foilsor light decoupling foils have been developed for LED light conductingtechnology. Typically these are foils based on poly carbonate with ahigh content of special ultrapure light scatter particles and with aspecial structure that is embossed onto the foil surface. For LEDs lightemitting diodes organic and organic systems OLED can be used. The foilis typically glued onto a glass surface at the LED housing. Specialfoils of this type for light conduction technology are sold e.g. byCovestro Deutschland AG, 41536, Dormagen, Germany. Under thedesignations Makrofol LM 327 (a light control foil or Makrofol TP 228 (alight decoupling foil). Makrofol® is a registered trademark. Lightcontrolling, light distributing and/or light decoupling foils areimprint able and deformable according to the HPF method into 3 D shapedelements without impairing the special surface structure. Also specialfoils of this type for light conduction technology can be used as a flatlaminate material for hot forming according to the invention.

Thicker metal layers or metallizations that are applied to laminatematerials that are used according to the invention can also be appliedby a printing method. Thinner metal layers with layer thicknesses of5-250 nm, in particular with layer thicknesses of 15-60 nm which providemetallic shine on the one hand side and which are light permeable on theother hand side can be applied by physical vapor deposition (PVD) orchemical vapor deposition (CVD). Superfluous metal layer sections thatare not required for certain graphical or decorative patterns can beremoved by laser treatment.

Suitable metals are e. g. aluminum, titanium, chromium, coppermolybdenum, indium and iridium and metal alloys like e.g. indium, tinalloys or copper alloys, advantageously indium, tin alloys, particularlyadvantageously indium, copper, tin alloys as described in e.g in thedocument US 2008/0020210. Furthermore at least one additional layer madefrom or plural electro luminescent compounds can be applied to the metallayers. Electro luminescent compounds of this type are known to a personskilled in the art e.g. from the document EP 1 647399 A1. In order toproduce electrically conductive paths pastes that include silverparticles can be applied or the metalizing recited supra can beperformed. LEDs (light emitting diodes) that are integrated into the 3dformed element can be connected to the conductive paths. Furthermorealso transparent sections can remain at the flat laminate element thatis to be formed wherein the liquid crystal display becomes visible lateron in the transparent sections.

On other surfaces that are arranged opposite to the color layerstypically a clear structured lacquer is applied which provides a matnon-reflecting surface to the finished product. After the 3D formedelement is arranged to perform its function the structure lacquer layerwill be arranged at a front side of the form element and the colorlayers of the graphic design will be at a back side of the formedelement depending on a viewing direction of a user.

Flat foils and plates made from the thermoplastic synthetic materialsrecited supra can be provided with a coating that is applied by coextrusion which provides particular properties and functions, among areabsorbs ion of UV radiation, color change, and/or darker colorationsusing photo chromic substance sunder an impact of sunlight, scratchresistant coatings with a dirt repelling function and “anti-gravityeffect” c.f. DE 10 2005 009 209 A1 (water absorbing coatings in order todelay/reduce water secretion in a humid environment “anti-fog” and otherknown functions. Typically coatings of this type have a layer thicknessof less than 50 μm.

Coatings can be subsequently applied to foils in plates made fromthermoplastic synthetic materials that have already been produced, inparticular one or plural protective layers. In particular for polycarbonate it is well known that it is not inherently UV stable byitself. Bisphenol A polycarbonate has maximum UV sensitivity between 320nm and 330 nm. Below 300 nm no sun radiation reaches earth and above 350nm the polycarbonate is insensitive so that no yellow discolorationoccurs. Therefore sufficient UV protection is desirable for a 3D formedelement that is intended for long term outdoor applications.Additionally am improvement of abrasion resistance, weather resistanceand general utility of PC surfaces is desirable.

For this purpose a scratch resistant coating can be applied in anadhesion and primer layer onto existing foils and plates which alsoprovides UV protection. A production of a respective products isdescribed e.g. in the document DE 10 2009 020 934 A1. Accordingly acoating of this type can be applied to substrates made frompolycarbonate, polyester carbonate, polyester poly phenyl ether, polyacrylate and poly methacrylate. Corresponding semi-finished productsmade from PC with a scratch resistant coating or hard coating of thistype are commercially available e.g. from Covestro Deutschland AG,41538, Dormagen, Germany under the trade name Makrofol TP 278 and byMacDermid Autotype Ltd., Wantage UK under the trade name XtraForm®.

A semi-finished product is commercially available that is provided witha protected foil and which only reaches its final properties after asingle stage or 2 stage UV curing process. The semi-finished produce iscan be deep drawn as a matter of principle. Typically however asemi-finished product of this type is damaged during thermoforming dueto the required forming temperature of 160° C. or higher so that suchsubstrates that are provided with a UV curable scratch resistant coatingare not formable under thermoforming conditions. By comparisonsemi-finished products of this type can be formed into attractive 3Dformed elements by the method according to the invention since lowerforming temperatures are being used and because the 2 stage formingfacilitates an attractive shape with substantially curved or camberedsurfaces. Only after the forming is finished a single stage or 2 stageUV hardening is performed.

3D formed elements made from polycarbonate are well suited for exteriorapplications and for an application as interior furnishings in motorvehicles.

The two stage forming according to the invention of a flat warm laminatecan also be used for coating a 3D carrier element. All objects aresuitable as 3D carrier elements which have a 3 dimensionally configuredsleeve or shell whose surface shall be coated with a firmly adheringlaminate. Typically the sleeve or shell is supported at a supportstructure which subsequently also provides mounting and attachment ofthe coated product at its location of use. Substrates and/or carrierelements of this type can be made of metal for example light metal likealuminum, magnesium or other alloys, synthetic material like e.g. athermos plastic synthetic material that is injection moldable like e.g.polyamide PA, acryl nitril butadiene styrol terpolymer (ABS) acrylesterstyrol acrylnitril (PA) acrylnitril terpolymer (ASA) polyoxymethylene(POM) polyvinylchloride (PVC) or polyarylsulfones (PSU), furthermorefrom wood and other stable and durable materials. For an application asinterior furnishings in motor vehicles 3D carrier elements of this typeincluding their support structure are typically fabricated in advance asintegral one piece injection molded pars and are typically made fromsynthetic materials like e.g. PA, ABS, ASA, POM, PVC, or PSU.

In order for a provided layer material to reliably and permanentlyadhere to the coated 3D carrier element the layer material has to betied to the 3D carrier element by a glue layer. A glue layer of thistype facilitates using laminates with a high reset force, forming of thelaminate into small curvature radii and a safe and reliable attachmentof the laminate material edges at the 3D carrier element, in particularalso at its undercuts.

According to the invention a 3D carrier element can be coated with alaminate wherein a two stage forming of the originally flat laminatematerial is performed wherein an alternative method variant is possiblein which a blank made from a flat laminate material is placed on atransfer foil and the transfer foil and the laminate blank are jointlyformed in to stages c.f. also claim 19. Only the transfer foil isclamped in a manner that separates the two forming tool halves pressuretight from each other between the contact surface at the lower formingtool half and the sealing surface at the upper forming tool half. Whenloaded with the fluid pressure medium under a pressure medium pressureof 20 BAR to 300 BAR the pressure fluid impacts the transfer foil andthe laminate blank supported by the transfer foil is pressed against the3D carrier element and molded. Blanks of this type can advantageouslyinclude layers made from metal, wood, for example burl wood veneer,leather, artificial leather or textile materials like e.g. woven andknitted materials and non-woven fabrics and similar in addition to alayer or plural layers made from a thermo plastic synthetic materialfoil. The blank can have a size that is adapted to the 3D carrierelement and does not have to fill the entire cross section of thepressure bell. An undesirable deposition of laminate material on or atforming tool elements can be limited. The transfer foil serves as acarrier for the laminate. The transfer foil can be made from a highlyelastic foil material which provides a surface increase by stretchingduring isostatic high pressure forming which are required for finalforming of the laminate blank at the 3D carrier element. Expansion,stretching and other loading of the laminate blank can be reduced evenfurther or substantially prevented. Typically a forming of the laminateblank without stretching can be provided. Transfer foils made frompolyolefin, like e.g. polyethylene thus in particular LDPE, orpolypropylene respectively with layer thicknesses of approximately80-500 μm or transfer foils made from thermoplastic polyurethane TPU,thus e.g. DESMOPAN foils distributed by DESMOPAN®) are well suitable andbeing advantageously used. After completion a transfer foil of this typecan be removed from the coated product or can remain on the surface ofthe laminate as an additional surface protection. The blank is typicallysupported at the transfer foil by a contact glue which can be removedwithout residuals from the visible side of the laminate. Suitablecontact glues are well known and commercially available. A good adhesionof the blank at the transfer foil transfers a portion of the extensionof the transfer foil that occurs during the forming of the transfer foilto the laminate blank and thus prevents undesirable wrinkling of theblank.

Glue systems and glue compounds for generating a glue interconnectionbetween the laminate blank and the 3D carrier element are well known toa person skilled in the art which can select from a plethora of suitablecommercial products.

A method is advantageous in which a one component glue compound isapplied only to the contact side of the laminate. Furthermore the gluelayer that is only arranged on the contact side of the laminate shall beprovided initially in a non-active condition which facilitates storageand handling. Through a controlled activation treatment the initiallynon-active glue layer shall be transferred into an active condition inwhich the gluing process is then started. An advantageous activationtreatment is the heating of the glue compound to its activationtemperature. In this case thermally activate able glue compounds or hotmelt glues are being used. An alternative or additional activationtreatment is irradiation with actinic radiation in particular UVradiation. In this case UV hardening glues are being used. In order toactivate the UV hardening glues additional UV radiators have to beprovided in the heating zone.

The application can be performed e.g. in that a solution, with anactivate able glue compound is applied through a silk screening methodon a contact side of the laminate material. Subsequently the solvent isremoved by evaporation and drying. A thin even dry layer made from gluecompound can be obtained which is typically only applied where gluingforce is required. Alternatively, an activate able glue compound can bepicked directly from a silicone release paper as a dry layer andtransferred, e.g. in that laminate material and release paper providedwith the activate able glue compound are jointly run through a calendarroller gap. Furthermore accordingly selected powder glues can be appliedby extrusion coating, e.g. by hot extrusion or powder coating or byanother direct coating. Various thermally activate able melt glues arealso available as melt glue foils or non-woven materials and can beapplied to the contact side of the laminate in this form, for example ina desired shape and size. Thermally activate able glue compounds, meltglues and hot melt glues are known to a person skilled in the art whocan select from many commercially available products, subsequentlyexemplary recipes are recited.

A thermally activate able glue compound can include an elastomeric basepolymer and a modification resin as essential components, wherein themodification resin includes a glue resin and/or a reactive resin. Theelastomeric base polymer can be a thermoplastic polyurethane or a mix ofpowdery polyurethane forming components like aromatic diisocyanaten andpolyester polyols with a high content end hydroxyl groups. Thermoplasticpolyurethane with a high content of end hydroxyl groups provide aparticularly high glue strength on various substrate. An alternative,thermally activate able glue compound can include:

-   -   50-95% by weight of a glue able polymer, and    -   5-50% of an epoxy resin and a mix of plural epoxy resins;

Wherein the glue able polymer includes acrylic acid compounds and/ormethyl acryl compounds and one or plural co polymerize able vinylmonomers.

Another thermally activate able glue compound can include:

-   -   40-98% by weight acrylic containing block polymer;    -   2-50% by weight of 1 or plural tackifying epoxy resins, and/or        nova lack resins and/or phenolic resins; and 0-10% hardener for        cross linking the epoxy resins and/or the nova lack resins        and/or the phenolic resins.

In order to provide optimum cross linking suitable initiators and/orcross linkers can be added to the glue compound, e.g. IR radiationabsorbing photo initiators and/or UV light absorbing photo initiators.Additionally adhesion enhancing compounds, e.g. so called primers can beprovided. For primers so called not seal glues based on polymers likee.g. ethyl vinyl acetate, and functionalized ethyl vinyl acetates andalso reactive polymers can be used.

Thermally activate able glue compounds of this type can be produced andadjusted so that an activation temperature in a range of 60-140° C.°,further advantageously an activation temperature of 75 to 130° C.Activation temperatures in this range are within or below the formingtemperature according to the invention for a particular laminate. Aftera cooling below this activation temperature at least a sufficientinitial glue strength between the layer material and the 3D carrierelement is obtained so that the contact pressure can be removed prettyquickly and the product can be retrieved from the forming tool. The hotlaminate is pressed against the carrier element and formed by a fluidpressure medium, in particular compressed air under a pressure mediumpressure of 20 BAR to 300 BAR for a sufficient time period e.g. 20-30seconds. When the liquid pressure medium is removed from the pressurebell quickly then the associated lowering of the temperature of theforming tool and of the coated carrier element facilitates a quickcooling of the glue layer below its activation temperature.

Further detail regarding the thermally activate able glue compounds canbe derived from the document DE 10 2006 042 816 A1. The describedthermally activate able glue compounds are advantageously used accordingto the instant invention. Thus thermally activate able glue compounds,melt glues and hot melt glues are advantageously heat able withinseconds to their activation temperature and develop and provide asufficient glue strength to the contact side of the laminate and to the3D carrier element surface within seconds of cooling. Heat activate ableglue compounds or hot melt glues sold by Covastro Deutschland AG, 41538,Dormagen, Germany under the tradename DESMOMELT (DESMOMELT®) are wellsuitable. This is a mix made from crystalline polyester polyols andcrystalline di isocyanates which form poly urethanes with end hydroxolgroups after heat activation. Good adhesions at different materials likefor example leather, textiles, wood fiber materials and numerous plasticmaterials including PUR elastomeric materials and soft PVC is achieved.Various desmomelt types can be processed for example as a solution inselected solvents (e.g. Butanon-@, acetone or methyl ethyl ketone can beprocessed as melt glue foils or directly as a powder by direct coating.The minimum activation temperature is 60° C. When loaded with highpressure fluid a sufficient initial glue strength is already obtainedwithin seconds wherein the glue strength increases further after aretrieval of the coated product from the forming tool during the nexthours.

The laminate that is provided with a partial or entire dry layer madefrom thermally activate able glue compound or melt glue has to be heatedenough before forming so that the glue compound or the melt glue isactivated. This is performed according to the invention together withheating the laminate to its forming temperature.

The laminate element that typically has ambient temperature is heatedbefore the 2 stage forming according to the invention to a formingtemperature that is specific to the respective synthetic material. Theforming temperature according to the invention is a function of theVICAT-softening temperature B50 or of the VST (Vicat softeningtemperature) B50 respectively according to DIN EN ISO 306 of therespective synthetic material. In order to determine the VST, a needlewith a circular frontal surface of one mm². Under a predetermined forceon a probe and a temperature is determined at which the needle onepenetrated 1 mm deep into the probe. In the variant B50 a force of 50 nis used and a heating rate of 50° C. per hour. For various syntheticmaterials a Vicat softening temperature B50 or VST B 50 is described inthe internet location http://wiki.polymerservice-merseburg.de “Vicatsoftening temperature-Encyclopedia of synthetic material testing. Thesubsequent table shows the VST B50 in ° C. for some synthetic materialsand recommended forming temperature for compressed air forming duringthermal forming (c.f. textbook “Thermoformen in der Praxis”, von PeterSchwarzmann, Publisher ILLIG, second edition, Carl Hanser Verlag,Munich, 2008, therein page 40).

Synthetic VST V Recommended forming temperature ° C. material 50 (° C.)according to ILLIG PC 145  150-180* PMMA 103 140-170 ABS 87 130-160 SAN106 135-170 PA 6 200 230-240 PS 84 120-150 PP 90 150-160 PVC-U 77120-140 *According to the invention thermoforming of PC semi-finishedproducts is performed at or mostly at forming temperatures of 180° C. to220° C.

According to the invention a heating to a forming temperature in atemperature range of [VST 50B (° C.) minus 20° C.) to (VST 50B (° C.)plus 23° C.)] is provided for the respective synthetic material. Furtheradvantageously a heating to a forming temperature in a temperature rangeof (−10-+15° C.) is provided about the respective VST 50B. Foils andplates made from polycarbonate (PC) are advantageously heated to aforming temperature in a temperature range of 130° C.-158° C. Theforming temperature that is provided according to the invention is thussignificantly below the forming temperatures that are provided and usedfor the thermo forming.

In order to perform the heating advantageously a touch free heating isperformed by radiation heaters under conditions where at least one sideof the entire mold surface or of the major portion of the mold surfaceof the laminate layer assumes a surface temperature in a temperaturerange recited supra. The preceding forming temperatures are surfacetemperatures that are measurable by a heat image camera.

In order to perform the processing according to the invention the flatlaminate element is applied to a frame carrier or a frame pallet orsimilar in a predetermined orientation. A frame pallet with a bar widthof 30 mm to 60 mm is particularly suitable. The edge sections of thefoil, the plate or the multilayer arrangement typically rests with awidth of 20 mm to 30 mm on the bars forming the frame shaped pallet.Circular positioning pins that protrude from the bars and engage slottedholes that are recessed in the laminate element edge sections provide adefined arrangement.

The pallet that is supported on a frame of this type is moved into aheating zone and is heated to forming temperature by radiation heating,touch free, e.g. using infrared radiators or quartz radiators.Advantageously a heating zone is provided which includes 2 heatingfields that have identical surface areas that are horizontally orientedand arranged in alignment with each other. The laminate element that issupported on the frame shaped pallet is centrally held for a certaintime period between and at an equal distance from both heating fields.Typically each heating field has a larger surface than the alignedarrangement of pallet and laminate element. Additionally each heatingfield can be enveloped by a circumferential skirt which is orientedtowards the laminate element that is to be formed and which reflects andfocuses the radiation of the edge heat radiator onto the laminateelement.

Each heating field includes a plurality of adjacent individuallycontrollable flat radiators or quartz radiators which form a heat shieldin combination. Advantageously rather small format infrared radiators orquartz radiators are being used. Full ceramic radiators with dimensionsof 60 mm×60 mm are quite well suitable which assume a surfacetemperature of approximately 300° C. with a power consumption 125 Watt.Infrared flat radiators of this type are available from FRIEDRICH FREKGmbH, 58708 Menden, Germany.

Typically a distance between the surface of the laminate element to beformed and a surface of the upper heat shield and on the other hand sideof the surface of the lower heat shield in a range of approximately 100mm to 130 mm is provided. This achieves an overlap of the respectiveadjacent edge portions of adjacent infrared flat radiators or quartzradiators with respect to the heat radiation. The impacts of the flatradiator boundaries are minimized, and an even temperature distributionis achieved at the forming surface of the laminate piece to be formed.

The amount of heat that is transferrable by the heat shield into thelaminate element is proportional to the fourth power of the heat shieldtemperature in ° K. The higher the heat shield temperature the shorterthe heating time, this means the required dwelling time of the laminateelement in the heating zone to achieve its heating to the formingtemperature. A rather low heat shield temperature provides moreflexibility for selecting the dwelling time which is important inparticular for heating plates in order achieve a sufficient heating ofthe plate core zone and facilitates a reaction to particularities of thelaminate surface caused e.g. a partial lettering, imprint, metallizationand/or other coating. According to the invention advantageously a heatshield temperature in a range of 120° C. to 180° C. above VST 50B of thesynthetic material to be formed is provided. This facilitates asufficiently long dwelling time of the plate to be heated in the heatingzone in order to sufficiently heat a plate core zone without damagingthe plate surface.

With foils with layer thicknesses of 100 μm-500 μm typically a heatingspeed of 5° C.-10° C. per second is reached. The foil surfacetemperature corresponds approximately to a foil core temperature. A corezone of foil or plate is presumed at 40%-60% of layer thickness. Forsynthetic material plates, e.g with layer thickness of 3 mm to 10 mm asignificantly lower heating velocity has to be presumed. Based on theboundary conditions recited supra good results were achieved when aplate that has ambient temperature is heated up to the formingtemperature during a dwelling time in the heating zone which isadvantageously:

-   -   for a plate with a plate thickness of 3 mm at least 70 seconds;    -   for a plate with a plate thickness of 6 mm at least 140 seconds;        and    -   for a plate with a plate thickness of 10 mm at least 230        seconds.

Further advantageously it is provided to keep the plate that is to beformed and that is introduced at ambient temperature into the heatingzone in the heating zone for a dwelling time that is a function of theplate thickness [(plate thickness in mm)×23 seconds+c)]. In order toheat the plate to the forming temperature; c has a value of 3-70,further advantageously 5-50. In plates thus heated also the core zonehas sufficient flexibility in order to be able to perform the monodirectional forming into a mono directionally formed blank also atthicker plates. It is advantageous when each infrared flat radiator orquartz radiator is individually controllable at the heating screenrecited supra. The controlling is performed by the electrical powerconsumption. A higher power consumption generates a higher surfacetemperature at a given infrared flat radiator or quartz radiator. Thus afine control of the temperature distribution can be performed at thesurface of individual portions of the form surface of a plate to beformed wherein the individual portions are associated with a particularinfrared flat radiator or quartz radiator additionally through thecontrol of power consumption of the individual infrared flat radiators.The effect of this fine control is the greater, the lower, the averagesurface temperature. Thus the heating of a plate to be formed isadvantageously performed in a heating zone which is defined by 2 alignedheating fields which have an average heating screen surface temperaturein a range of 120° C.-180° C. above VST B50 of the synthetic material tobe formed from which the plate to be formed is made.

In order to achieve optimum results a rather precise control andmeasuring of the surface temperature is helpful at the section of aplate that is to be formed. In order to detect the surface temperaturethe plate that is heated in the heating zone can pass a temperaturemeasuring station on a path from the heating zone to the forming zone,wherein a temperature distribution at a plate surface is scannedvisualized or represented in another way by a heat imaging camera touchfree.

This configuration of the method according to the invention achieves thesubsequent advantages.

Ceramic infrared radiators of the type used herein emit their heatradiation in a wave length range of 2.5-10 μm. The heating of the plateis a function of absorption properties of the plate material and ofreflection properties of the plate surface in this wave length range. Acoating of the entire plate surface that is applied by co extrusionand/or the imprinting metalizing or other coating of a portion of theplate surface that follows a predetermined layout can significantlyinfluence and change a plate surface temperature that is achieve able bya predetermined heat radiator surface temperature within a predeterminedtime span. A transparent plate material and/or a light colored coatingsections reduce the heat absorption. In particular a metal coating thusmade from AL, TI or CR can significantly reduce heat absorption. On theother hand side a dark to black coating section increases heatabsorption. A plate surface temperature that is achievable in apredetermined arrangement with predetermined infrared flat radiatorswith in a predetermined time period is also a function of type and sizeof the imprint, metalizing and/or other coating of the plate sectionthat is provided for the forming. Controlling individual infrared flatradiators can compensate these differences in order to achieve a uniformand even plate surface temperature. it can be furthermore desirable tomake the plate material more flexible in individual plate sections wherea particularly strong or particularly sharp edged forming is providedabout a small curvature diameter which is achieved by a higher platesurface temperature in these locations. For this purpose in particularplate segments can be selected where a particularly strong monodirectional forming of the originally flat plate shall be performed.

In view of the forming temperatures in a range of (−10° C. to +23° C.)about VST 50B of the respective thermoplastic synthetic material e.g. byabout 130° C.-158° C. for 3D formed elements made from polycarbonate(PC) or about 90° C.-120° C. for 3D form elements made from poly (meth)acrylate (PMMA). Typically an infrared line camera is suitable as athermal imaging camera which is configured for a temperature range of 0°C.-400° C. and which captures and processes temperature radiation in awave length range of 8 μm-14 μm. Detecting the heat radiation isperformed by a line sensor which can have e.g. 128 or 136 measuringelements. Infrared line cameras of this type with a correspondingprocessing circuit and processing software are commercially available.An infrared camera is proven particularly useful in the context of theinstant invention which is sold by DIAS INFRARED GmbH, 01217, Dresden,Germany under the trade name INFRALINE®.

This infrared camera INFRALINE® is used for capturing temperaturedistributions touch free in a quantitative manner and substantiallyirrespective of distance at fixed objects and moving objects. The camerawas developed for stationary applications in industrial environments andis useable for system solutions for automated process control andmeasuring data processing at machines and equipment. The camera is madefrom a camera head that includes modules that are required foroperations. Due to the typically remote installation of the cameraproximal to a process to be monitored or the objects to the monitoredthe camera does not have any operating elements. In order to providecontrol, monitoring and measuring value transmission a data interface isintegrated into the camera. The programming and measuring value capturecan be performed in a conjunction with a PC. In order to illustrate andprocess measuring data the visualization software PYROSOFT® that isprovided by MICROSOFT INC., can be advantageously used which is capableto run PCs with the MS-window operating system. Based on color codingand numbers the measured temperature can be displayed with a precisionof 1/10° K.

Based on the knowledge regarding the “actual” temperature distributionat a heated surface of a plate to be formed. Infrared flat radiatorswith a higher electrical power can be controlled to heat plate segmentswhich have not reached the predetermined plate surface temperature sofar e.g. due to particularities of the imprint, metallization, and/orother coating.

It is not necessary that the method step “measuring a processing thetemperature distribution at the plate surface” is performed during theentire production process for producing all 3 D form elements of aparticular type. Quite frequently it is sufficient when this method stepis performed when setting up a production line and repeated subsequentlyafter generating a predetermined number of 3D form elements in order toassure even uniform quality of the 3D form elements. Typically it issufficient when this method step is only performed when producing atleast 20% of all 3D form elements of one type that are to be produced.After the laminate element to be formed has been heated within the heatstation to the desired surface temperature the hot laminate element isquickly transferred from the heating station into the forming stationwithout a significant cooling. Even when the laminate element passes thetemperature measuring station on a path from the heating station to theforming station and the temperature distribution at a bottom side isscanned, visualized or otherwise displayed by a thermal imaging camerathe laminate element is transferred into the forming station immediatelyafter completing is dwelling time advantageously within a time period ofless than 5 seconds, particularly advantageously within a time period ofless than 2 seconds and particularly advantageously within a time periodof 1 second wherein mono directional forming of the hot flat laminateelement is initially performed in the forming station.

In the forming station the two stage forming of the hot flat laminateelement is performed according to the invention into the 3D form elementor its coating onto the 3D carrier element. For this purpose a presswith a forming tool can be advantageously used as described in thedocuments DE 10 2010 021 892 B4, DE 10 2008 050 564 B4 and DE 41 13 568C1. These documents are incorporated in the instant application by thisreference in as far as they are helpful to understand and configure theforming tool according to the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is subsequently described in more detail with reference toadvantageous embodiments. Based on advantageous embodiments withreference to drawing figures, wherein:

FIG. 1 illustrates a flat base material and a mono directionally formedblank obtained after mono directional forming with predetermineddimensions in order to illustrate the term “mono directional forming” ina cartesian coordinate system.

FIG. 2A illustrates perspective view of a flat laminate element to beformed;

FIG. 2B illustrates a perspective view of a flat arrangement of a pieceof transfer foil at which a laminate blank adheres that is provided witha glue layer;

FIG. 3 illustrates a slanted view of a frame shaped pallet;

FIG. 4 illustrates a slanted view of a transport frame;

FIG. 5 illustrates a perspective view of a laminate element according toFIG. 2A on a frame shaped pallet according to FIG. 3;

FIG. 6 illustrates perspective view of a laminate element and a palletaccording to FIG. 5 on a transport frame according to FIG. 4;

FIG. 7 illustrates a schematic view of essential components of anarrangement for performing the method according to the inventionincluding a loading station and an unloading station, a forming station,a heating station and optionally a temperature measuring station;

FIG. 8 illustrates a schematic side view of a forming tool according tothe invention;

FIGS. 8A and 8B illustrates details of FIG. 8 illustrating a selectedsealing device;

FIG. 9 illustrates a perspective view of the forming tool according toFIG. 8;

FIG. 10 illustrates a schematic perspective view of an interior of theforming tool, wherein in particular the non-flat sealing surface contourat the upper forming tool half and the congruent non-flat surfacecontour at the frame superstructure at the lower forming tool half isemphasized;

FIG. 11 illustrates a top view of the pallet frame and the transportframe and the contact surface of the frame shaped super structure infront of the mold carrying substructure at the lower forming tool half;

FIG. 12A illustrates an isolated mono directionally formed blank that isremoved from the forming tool and merely represents an intermediaryproduct;

FIG. 12B illustrates a schematic representation of a cut along thesectional line XIIb-XIIb of FIG. 12A;

FIG. 13A illustrates a schematic side view of a finished productaccording to embodiment 1; and

FIG. 13B illustrates a cross section in width direction through thefinished product according to FIG. 13A

DETAILED DESCRIPTION OF THE INVENTION

In a cartesian coordinate system with three directions in space (X), (Y)and (Z) a rectangular flat laminate element E is provided in the X,Y-plane, which has longer sides (F) parallel to the X axis and shortersides (G) parallel to the Y axis. This flat laminate element E isprovided with a grid with parallel straight lines (F1-Fn) which haveuniform distances from each other and which are oriented parallel to thesides F and with straight lines (G1-Gn) that have uniform distances fromeach other and which are oriented parallel to the sides G. an impact of2 offset fixed, identical non-flat contours, thus e.g. a partiallycircular contour at a circle with a radius r=30 mm on two opposite edgesections that are oriented parallel to the X axis and offset from eachother of the flat laminate element E on one axis to the X, Y plane, thusin the Z direction and only in the Z direction, thus mono directionallycauses a mono directional forming of the flat laminate element E into amono directionally formed blank (V) which additionally has an extensionin the Z-direction. According to the auxiliary drawings the cord S has alength of 50 mm for a central angle of 120° and the circular arc (b) hasa length of 63 mm according to the known formula b=(α πr)/180 c.f.KLEINE ENZYKLOPAEDIE—Mathematik VEB BIBLIOGRAPHISCHES Institut 50 mm and(b) INSTITUT LEIPZIG, 1967, page 203). And therefore the monodirectionally formed blank (V) has a length in the X-direction that is13 mm less than the originally used flat laminate blank E. Consequentlythe portions of the original flat laminate element E that have more orless distance from the apex point S have to move in X direction more orless towards this apex point S with a corresponding displacement of thelaminate elements and therefore the displaced laminate elements have tobe able to slide on a base that includes the original flat element E. A“mono directional forming” is characterized in that the originalstraight lines (F2-Fn) at the mono directionally formed blank (V) nowhave become cambered lines H2-Hn, whereas the original straight linesG1-Gn have been kept as straight lines G1-Gn with the original length.Consequently the mono directional forming of the flat laminate element Ein X direction has not caused any forming of the flat laminate element Eand displacement of the laminate particles in the orthogonalY-direction.

Ideally this mono directional forming does not cause any increase of thesurface the original flat laminate element E, thus it is performedwithout stretching. As long as the mono directional forming according tothe instant invention is performed by 2 fixed substantially identicalcontours a no stretch or low stretch mono directional forming can beobtained at which a surface area increase at the original flat laminateelement of up to 4%, advantageously up to 2% and particularlyadvantageously up to 1% of the original surface area can occur.

A flat laminate element shall be hot formed. Advantageously arectangular laminate element 3 is provided that is illustrated in FIG.2A and which includes parallel offset longitudinal sides 4′ and 4″ andtransversal sides 5′ and 5″. A first laminate direction R in which thelaminate element 3 is not clamped on its bottom side but can slide istypically oriented parallel to the longitudinal sides 4′, 4″. Thelaminate element 3 has a circumferential edge zone 6 which includesparallel offset opposite edge sections 7′, 7″ at the longitudinal sides4′, 4″. The edge zone 6 envelopes a formed surface at which the formingis performed. According to the subsequent embodiment 1 a flatrectangular laminate element 3 made from polycarbonate is formed whichhas a length of 1200 mm and a width of 200 mm.

When coating a 3D carrier element an alternative base material that isillustrated in FIG. 2B can be provided which includes a carrier ortransfer foil 10 that is provided with an edge zone 6 at which alaminate blank 11 adheres that is adapted to the 3D carrier elementwherein a surface of the laminate blank that is oriented away from thetransfer foil 10 is covered with a layer 12 made from an activate ableglue. In case of forming and coating a 3D carrier element thealternative base material assumes an arrangement in the forming tool inwhich the glue layer 12 is oriented downward towards the 3D carrierelement to be coated. In this case when coating a 3D carrier element thestatement “flat laminate element” shall also include a flat arrangementmade from a transfer foil 10 at which a laminate blank 11 adheres thatis covered with a layer 12 made from activatable glue.

The hot forming of the laminate element 3 is performed in an arrangementthat is illustrated in FIG. 7 and includes a known loading and unloadingstation A, a forming station B, a heating station C and optionally atemperature measuring station D. A straight rail pair 15 runs throughthe entire arrangement. A transport frame 20 illustrated in FIG. 4 runson this rail pair 15 wherein the transport frame has a closed, wide flatplanar frame 21 that envelops a recess 22. The frame 21 is formed insteps so that a circumferential support 23 is provided that is directedinward towards the recess 22. Two “endless” timing belts 24′ and 24″ areattached at a front end 25 and at a rear end 26 of the frame 21. Thesetiming belts 24′ and 24″ mesh with non-illustrated cogs which are drivenby step up motors that are configured for a high acceleration and feedvelocity in order to run the transport frame 20 along the rails 16through the arrangement. For example the transport frame 20 can beadjusted with a velocity up to 1,400 mm per second along the rails 15.

The laminate element 3 to be formed is placed in the loading station andunloading station A on a frame shaped pallet 30 that is illustrated inFIG. 3 which in turn can be placed on the contact surface 23 at thetransport frame 20. The frame shaped pallet 30 has a closed flat planarframe 31 which envelopes a recess 35. A number of protrusions 33 thatprotrude inward in a direction towards the recess 35 are integrallyformed at an inner circumference 32 of the frame 31 in uniformdistances. The circumferential edge zone of the laminate element 3 or ofthe transfer foil 10 is placed on these protrusions 33. This placementis performed in the loading station and unloading station A and can beperformed manually or by an automated device. A respective verticallyprotruding mandrel 34 can be provided at selected protrusions 33 whereinthe mandrel engages bore holes or slotted holes in the edge zone 6 inorder to assure a defined arrangement of a laminate element 3 at theframe shaped pallet 30. The length of the slotted holes extends in thefirst laminate direction R in order not be impede a sliding of the edgezone 6 on this frame 31 when the laminate element 3 partially lifts offfrom the frame 31. Guide rings 37 can be arranged at the frame 31,wherein mandrels 53′, 53″, 53′″ enter into the bore holes wherein themandrels protrude vertically from a lower forming tool half 50 in orderto assure a precisely fitted arrangement of the frame shaped pallet 30with the laminate element 3 to be molded thereon with respect to a mold55 or a 3D carrier element which is fixated at the lower forming toolhalf 50.

The frame shaped pallet 30 (e.g. FIG. 5) that is provided with the flatlaminate element 3 is placed on the circumferential support 23 at thetransport frame 20 c.f. FIG. 6 and the transport frame is moved alongthe rails 15 from the loading and unloading station A—the formingstation B into the heating station C. In the heating station C there isa heating arrangement 40 in which the flat laminate element 3 that ismade from the thermo plastic synthetic material and which has ambienttemperature is heated to a predetermined forming temperature that isadapted to the respective synthetic material. Typically an infraredradiation heater is used and the heater arrangement 40 has an upperheating field 41 and an offset lower heating field 42 between which thetransport frame 30 with the laminate element 3 to be heated is inserted.Both heating fields 41 and 42 are configured with identical surfaces andarranged in alignment with each other at a distance of approximately 250mm. As indicated in FIG. 7 each heating field surface can be greaterthan the frame surface of the transport frame 20. Each heating field 41and 42 can be made from a number of infrared flat radiators 44 whichrespectively have dimensions of 60×60 mm and which are individuallycontrollable. An opposite infra-red flat radiator 45″ at the lowerheating field 42 can be associated with an infrared flat radiator 45′ atthe upper heating field 41.

After the laminate element 3 has reached the predetermined formingtemperature or has exceeded it slightly the transport frame 20 is movedquickly from the heating station C back into the forming station B. Thisway an optional temperature measuring station D can be passed in which athermal imaging camera 47 is arranged which captures and processes atemperature radiation 48 that is emitted by a bottom side of the formingsurface 8 of the laminate element 3. The temperature distribution thuscaptured can be displayed on a non-illustrated screen wherein arespective image on the screen can be associated with each alignedinfrared flat radiator 45′, 45″. The actual temperature that is providedat a surface of the laminate element bottom side can be represented by acolor encoding and/or by numbers.

In the forming station B there is a press 100 with a forming tool 49 towhich a compressed air container 100 is connected from which compressedair is provided. The press 10 and the forming tool 49 can be essentiallyof a type that is also described in the documents DE 10 2008 050 564 B4and DE 41 13 568 C1.

FIGS. 8 (side view) 9 (perspective view) and 10 (reduced perspectiveview) show a forming tool 49 that is suitable for performing the 2 stageforming according to the invention of the hot flat laminate element 3 inits release position. As evident in detail from FIGS. 8 and 9 theforming tool 49 is essentially made from an upper forming tool half 80and a lower forming tool half 50 which is arranged below the upperforming tool half 80 and which is supported on a lower forming table 105of a press 100 and which is supported at the vertically oriented columns101 of this press 100. This lower forming tool half 50 is associatedwith a carrier plate 51 and a base plate 52 on which a base 54 issupported at which the actual mold 55 is attached whose mold contours56′, 56″ and 56′″ perform the high pressure forming of the monodirectionally formed blank. Alternatively the 3D carrier element can beattached at this substructure 54 wherein the hot mono directionallyformed blank shall be coated onto 3D carrier element contours of the 3Dcarrier element. The base plate 52 can be advantageously provided with aheating arrangement which in turn includes a circulation system for aheating liquid or heating wires and a control arrangement for keepingthe temperature constant. Furthermore a non-illustrated layer made froma thermally insulating material can be arranged between the carrierplate 51 and the base plate 52. Thus the temperature of the lowerforming tool half 50 can be adapted to the forming temperature of thehot laminate element 3 to be formed.

A substructure 54 of this type has to be configured massive and attachedin a stable manner in order to sustain the substantial mechanicalpressure loading. In case of coating a 3D carrier element a new 3Dcarrier element has to be attached at this substructure 54 anddisengaged again after coating.

For this purpose a fold able substructure 54 can be provided whichincludes at least one non-illustrated slide which is configured extendable and retract able, arranged and actuate able. Extending the moveable slide can be performed e. g. hydraulically or pneumatically againsta spring force which is configured to retract the slide. The extendedslide reaches behind a retention bar or an undercut at the applied 3Dcarrier element and assures its support at the sub structure 54. Thisachieves on the one hand side a secure and stable attachment and on theother hand side easy disengagement of the 3D carrier element at the fromthe substructure 54. After performed the coating and achievingsufficient glue strength an extended slide is run back or pulled in andthe coated 3D carrier element can be removed from the sub structure 54easily. Inserted the 3D carrier element and removing the coated 3Dcarrier element can be performed by hand or by an automated machine.

The substructure 54 with the mold 55 or with the 3D carrier element isenveloped by a closed clamping frame which is supported on the baseplate 52. A clamping frame 52 can be used that is supported on the baseplate 52. Alternatively a clamping frame with sprig suspension thismeans a so called spring frame 57 can be used which is supported at thebase plate 52 by compression springs 58. A spring frame 57 of this typeis illustrated in FIGS. 8 and 9. The subsequent statements regarding thespring frame 57 however relate equally to a clamping frame that issupported at the base plate 52.

At a spring frame 57 (or clamping frame) the two non-flat contours arearranged which contact the 2 parallel offset opposite edge sections 7′,7″ of the hot flat laminate element 3 that rests on the frame shapedpallet 30 in order to form the flat laminate element 3 into a monodirectionally formed blank W.

In an advantageously embodiment that is illustrated in FIGS. 8 and 9 thespring frame 57 or the clamping frame has a massive closed flat framewhose outer dimensions are identical or slightly less than the outerdimensions of the frame shaped pallet 30 so that the frame 60 can reachunder the frame shaped pallet 30 and lift it within the transport frame20 that is held in place. This frame 30 has a circumferential edge zone.The frame 60 is replace ably arranged at the lower forming tool half 60.A height of the frame 60 corresponds to a height of the substructure 54plus the mold 55 or the height of the sub structure 54 plus the 3Dcarrier element, so that the frame 60 is adaptable in so far to theemployed mold 55 or the 3D carrier element to be coated. When this frame60 has reached its upper dead center then the bottom side of the frameshaped pallet 30 contacts its edge zone 61 wherein the frame 60 haslifted the pallet with respect to the locally fixated transport frame bya small amount. When the clamping frame is supported directly at thebase plate 52 then the upper most point of the mold contours 56′, 56″ or56′″ or of the 3D carrier element contours contacts a bottom side of themono directionally formed blank or is slightly below in thisarrangement. When using the spring frame 57 the press 100 can lift thebase plate 52 with respect to the fixed frame 60 by a small distance,wherein the compression springs 58 are compressed and the base plate 52with the substructure 54 moves even closer to the blank that is clampedin place so that the form contours 56′, 56″ or 56′″ or the 3D carrierelement contours penetrate through the bottom side of the blank at leastpartially and provide at least a certain orienting “mechanical” positiveforming to the clamped blank like a plunger wherein the positive formingis subsequently supplemented and completed by the high pressure forming.

The two non-flat contours that cause the mono directional forming arearranged at this frame 60 and can be configured e.g. integrally in onepiece further advantageously a replace able frame superstructure 62 thatis adapted to the respective product to be produced wherein the superstructure includes 2 flat end sections 63′ and 63″ with 2 parallel andoffset side walls 64′ and 64″ which are oriented orthogonal to the endsections 63′ and 63″ and which include a flat bottom side which can beapplied to the frame 60 and attached thereon. This frame superstructure62 has a circumferential upward oriented face which is used as a contactsurface 65 for the edge zone 6 of the laminate piece 3 that is to be hotformed.

Each side wall 64′ and 64″ has a face section which is respectively usedas a contact surface section 66′ and 66″ for a respective edge section7′ and 7″ of the laminate element 3 to be formed. Each contact surfacesection 66′ and 66″ is configured as an identical or substantiallyidentical contour 67′ and 67″, e.g. starting with a flat end section 63′then rising gently to an apex point 69 and then descending again gentlyto another opposite flat end section 63″. The two non-flat contours 67′and 67″ form the non-flat contact surface contour 68 at the lowerforming tool half 50, advantageously the two contact surface sections66′ and 66″ are arranged at both longitudinal sides of thesuperstructure 64 or at the 2 longitudinal sides of the clamping frameor of the spring frame 57. In the instant case as illustrated in FIGS. 8and 9 this non-flat contact surface contour 68 protrudes relative to theremaining flat contact surface sections 63′ and 63″ or is configuredconvex and has a centrally arranged apex point 69.

In this embodiment illustrated in FIGS. 8 and 9 this apex point 69 canhave e.g. a height of approximately 80 mm to approximately 120 mm abovethe flat bottom side of the frame superstructure. The bottom side orbase surface of the frame super structure 62 has exterior dimensionsthat fit into the recesses 35 at the frame shaped pallet 30. The outercircumference of the frame shaped super structure 62 is aligned with theouter circumference of a subsequently described circumferential cavitywall 83 of a pressure bell 82 at the upper forming tool half 80.

Furthermore the forming tool 49 has an upper forming tool half 80 whichincludes a cover plate 81 which is supported in a press 100 at an upperform table 107. A pressure bell 82 is configured at this cover plate 81which forms a downward open cavity which has a circumferential cavitywall which is defined by a lower face which forms a circumferentialsealing surface 85 of the upper forming tool half 80. In this sealsurface 85 a circumferential groove 89 is recessed at a small distancefrom the cavity of the pressure bell 82 wherein a strand shaped sealingdevice is insert able into the circumferential groove wherein the strandshaped sealing device seals the cavity of the pressure bell 82 pressuretight relative to the blank when contacting the top side of the monodirectionally formed blank.

When the form surface is smaller than 800 cm² at the hot formed laminateelement 3 typically no larger curvature changes will occur at the archof the pressure bell 82 when loaded with pressure from the high pressurefluid so that a typical O ring made from an elastic circular thread witha diameter of approximately 3 mm-6 mm will suffice as a sealing device.In order to implement a form surface of at least 800 cm² the press andthe pressure bell have to be configured for a maximum pressure mediumpressure of 300 bar for at least a mold closing force of 24 mega Newton.The press and the pressure bell move under these tremendous forces and acertain amount of bending and warping can occur which would drive acircular seal that is more than 100 cm long from its groove. In order tostill provide a pressure tight sealing of the pressure bell a moreeffective sealing device has to be used under these severe operatingconditions. For this purpose a strand shaped profile seal 90 is providedwhich includes a body 91 that is insertable into the groove 89 whereinat least a first integrally seal lip 92 protrudes from the body 91 andis defined by an outer seal lip flank 93 and by an inner seal lip flank94. The inner seal lip flank 94 is arranged at a slant angle withrespect to the seal surface plane so that fluid pressure mediums thatflow in under a pressure of 20 bar to 300 bar and impact the inner seallip flank 94 deform the seal lip 92 elastically and press it against thelaminate 3. Using this particular type of strand shaped profile seal 90also forming tools with a comparatively large forming surface of 2000cm² and more e.g. with a forming surface of at least 3400 cm² or morecan be safely sealed so that also rather large laminate elements can beformed in this forming tool and coated onto rather large 3D carrierelements which can e.g. have a length of 100 cm or more. Further detailsregarding a strand shaped profile seal of this type can be derived fromthe document DE 10 2008 050 564B4 which is incorporated in its entiretyby this reference with a description of a strand shaped profile seal ofthis type.

A channel 96 leads into the cavity of the pressure bell 82 wherein afluid pressure medium can be introduced into the cavity of the pressurebell 82 through branches 97 of the channel 96 and removed againtherefrom. Merely schematically indicated control device 98 control thepressure medium supply and the subsequent ventilation. The fluidpressure medium that is supplied through the channel 96 can have anincreased temperature in order to counter act a cooling of the hotlaminate element 3.

It is a particular feature of the invention that the pressure bell 82has a respective sealing surface section that includes a non-flatcontour in addition to the flat sealing surface sections at both endsections of the pressure bell 82 at the sealing surface 85 at 2 paralleloffset opposite pressure bell sections 84′ and 84″ forming an identicalor substantially identical non-flat contour 87′ and 87″ and bothtogether form a non-flat sealing surface contour 88 at the upper formingtool half 80. Advantageously the 2 sealing surface sections areconfigured at both longitudinal sides of the pressure bell 82. In theillustrated case and as illustrated in FIGS. 8, 9 and 10 this sealingsurface contour 88 is configured concave and has a centrally arrangedvalley. This non-flat sealing surface contour 88 at the upper formingtool half 80 is configured congruent to the non-flat contact surfacecontour 68 at the lower forming tool half 50 so that a narrow gap can beformed between the two contours 88 and 68.

When the lower forming tool half 50 is lifted relative to the upperforming tool half 80 by the press 100 the frame structure, the framestructure 62 at the clamping frame or spring frame 57 that is arrangedwithin the recess 35 of the frame shaped pallet is lifted with respectto the frame shaped pallet 30 that rests fixed in place on the transportframe 20, wherein the super structure contact surface 65 includingnon-flat contact surface contours 67′ and 67″ reach under the paralleloffset and opposite edge sections 7′ and 7″ of the laminate element 3and move them along and eventually move them proximal to the congruentseal surface 85 including the non-flat contours 87′ and 87″ at thepressure bell 82, wherein the entire hot flat laminate element 3 isformed between the congruent non-flat contours 58 and 88 monodirectionally into a mono directionally formed blank W.

Due to the lifting movement of the lower forming tool half 50 the formedblank in lifted until its edge zone 6 contacts the sealing device. Thesealing device seals the laminate element 3 pressure tight relative tothe pressure bell 82 so that high pressure fluid that flows into thecavity of the pressure bell 82 applies and presses the blank against theform contours 56′, 56″, 56′″ of the form 55 or against the 3D carrierelement contours.

In case the forming tool 49 shall be used to form a laminate element 3with a form surface 8 that is significantly larger than 800 cm2, thelower forming tool half 50 is lifted until a narrow gap is formed in theclosed position of the forming tool 49 between the sealing surface 85including the non-flat sealing surface contour 88 at the upper formingtool half 80 and the contact surface 65 including the non-flat contactsurface contour 68 at the lower forming tool half 50, wherein the gapcan be bridged by the seal lip 92 at the strand shaped profile seal 90.Pressure fluid that flows into the pressure bell 82 distorts the elasticseal lip 92 at the strand shaped profile seal 90 that is inserted intothe groove 89 and presses the seal lip 92 against the top side of theblank and thus seals the cavity of the pressure bell 82 pressure tightrelative to the blank. The pressure fluid that flows into the pressurebell 82 thereafter presses the hot blank against the form contours 56′,56″, 56′″ of the form 55 or coats the blank onto the 3D carrier elementcontours. This gap typically has a width of [layer thickness of thelaminate element 3 to be formed+(100 μm to 1200 μm)].

The forming tool 49 described supra is inserted into a press 100 whichis described in more detail in the document DE 10 2008 050 564 B4 whichis incorporated in its entirely by this reference. The press 100 has aso called 4 column frame with four vertical columns 101 arranged atcorners of a square or rectangle, wherein the upper form tool half 80and the lower form tool half 50 are move ably supported at the columns101. The straight rails 15 that extends through the entire arrangementare run within the forming station B between a respective column pairmade from 2 offset columns 101. The transport frame 20 with the hot flatlaminate element 3 to be formed wherein the transport frame is supportedwithin the forming station B at the rails 15 forms a fixed arrangementrelative to which the components of the lower forming tool half 50 formrelative movements during adjustment.

At the forming tool 49 according to the invention also the upper formingtool half 80 is liftable by a significant distance in order to be ableto also retrieve 3D formed elements or coated 3D carrier elements with avery pronounced geometry from the intermediary space between the sealsurface 85 at the raised upper forming tool half and the transport framethat is held in place after high pressure forming. This lifting travelcan have e.g. a length of 100 mm and more. The length of the outerthread sections 103 at the upper sections 102 of the four columns 101 isadapted accordingly.

FIG. 11 schematically illustrates a view from above onto a transportframe 20 that is supported at the 2 rails 15 wherein a frame shapedpallet 30 without laminate element 3 is arranged on the transport framewherein the transport frame and the pallet are both arranged in theforming station B above the forming tool half 50. It is evident that theflat frame shaped pallet 30 has a frame 31 which includes a plurality ofoffset inward oriented protrusions 33 at an inner circumference 32 ofthe frame 31. A flat laminate element 3 that is to be placed on a frameshaped pallet 30 is placed with its edge zone 6 only on the protrusions33.

Within and below the recess 35 at the frame 31 of the pallet 30 thecontact surface 65 of a frame super structure 62 is visible at the frame60 of the spring frame 57. This super structure 62 has opposing sidewalls 64′ and 64″ respectively with a structured outer surface 70 andrespectively with a face which forms a contact surface 65 where recesses74 and outward protruding bars 76 are arranged at this structured outersurface. The resulting external circumference of the super structure isadapted to an inner circumference 32 at the frame 31 of the frame shapedpallet 30 so that

-   -   this super structure 62 is moveable at a close distance from the        inner circumference 32 of the pallet frame 31 with respect to        the pallet 30 that is held in place,    -   the protrusions 33 at the inner circumference 32 of the pallet        frame 31 engage recesses 74 at the outer circumference 72 of the        tension frame or of the spring frame 57 or of the frame assembly        62;    -   the protruding bars 76 at the outer circumference 72 at the        tension frame or the spring frame 57 or the frame assembly 62        engage the intermediary spaces between two respective adjacent        protrusions 33 at the pallet frame 3; and    -   when lifting the tension frame or the spring frame 57 or the        frame assembly 62 relative to the pallet 30 that is fixed in        place the protruding bars 76 at the outer circumference 72 of        the tension frame or the spring frame 57 or the frame assembly        62 reach below the rim sections 7′ and 7″ of the flat laminate        element 3 and move them along so that they deposit the laminate        element 3 on the contact surface 65 at the tension frame or at        the spring frame 57 or at the frame assembly 62,    -   so that during an additional lifting of the tension frame or of        the spring frame 57 or of the frame shaped super structure 62        with respect to the fixated upper forming tool half 80 the        laminate element 3 is formed monodirectionally into a mono        directionally formed blank W between the non-flat contact        surface contour 68 and the congruent non-flat sealing surface        contour 88.

Performing the method according to the invention according to theembodiment 1 with a blank W illustrated as a non-insolated intermediaryproduct is illustrated in FIG. 12A because this type of blank cannot beillustrated easily within the machine drawing. This blank W has aslightly cambered section adjacent to two flat end sections 5′ and 5″wherein the slightly cambered section starts at point P and terminatesat point Q and has a central apex point which reaches an apex height “h”over a cord “s” that connects the two points P and Q with each other. Atthe blank W an apex height “h” of 73.5 mm is obtained for a length ofthe cord “s” of approximately 700 mm. This yields a camberration=(h×100%)/s of 10.5%. This is a remarkable result for a foilelement made from thermoplastic synthetic material that is formedwithout stretching. It is evident that cambered foil elements that areformed without stretching can be obtained according to the inventionwith an even larger camber ration.

Embodiment 1

As a final product a metal a trim strip with a metal shine shall beprovided for the dashboard of an often SUV that is developed by a Germanpremium manufacturer. This trim piece has dimension of 1030 mm×85 mm andhas a three-dimensional shape or geometry in the longitudinal direction(longitudinal contour) and in the width direction (width contour). Thelong contour follows a slightly convex curvature with a central apexpoint which reaches a height of 73.5 mm above a plane of the two endsections. A side view of this longitudinal contour is illustrated inFIG. 13A. The width contour has several waves with a maximum distance of22.9 mm between a wave valley and a wave ridge. This width contour isillustrated in FIG. 13B according to scale in a sectional view in widthdirection through a 3D-foil element that is produced according to theinvention.

A PC foil that is coated with a black cover lacquer with a foilthickness of 550 μm is used as a base material for a test. As analternative base material, a highly transparent OPTO 4D-foil made byIsosport Verbundteile GmbH, 7000 Eisenstadt, AT, has been used with goodsuccess.

From the PC foil a flat, rectangular foil element with a length of 1270mm and a width of 260 m has been cut. This foil element has a formsurface of 1200 mm×200 mm within its edge zone. The forming is performedin a machine that is developed and built by NIEBLEIN GMBO, 82377,Penzbert, Del., and which is configured and equipped as illustrated inFIG. 7. The forming tool is essentially configured according to FIGS. 8,9, 10 a and 10 b for a form surface of 1200 mm×200 mm.

The heating station has two heat shields that have identical surface andthat are equipped with infrared flat radiators which are arranged at adistance of 250 mm from each other. Each heat shield surface exceeds thefoil element surface. Each heat screen surface both heat screens arekept at a temperature of 300° C. The foil element that has ambienttemperature is arranged resting on the pallet frame and the pallet frameresting on the transport frame centrally between the two heat screensand heated within approximately 10 seconds to a surface temperature of158° C. After reaching the forming temperature the hot foil element ismoved back within two seconds into the forming station and arranged inthe forming tool that is in its release position. The lower forming toolhalf is raised and reaches its closing position in approximately onesecond, wherein the lower form table raises the frame structure arrangedthereon, wherein the two non-flat contact surface contours reach underto parallel offset opposite edge sections at the hot foil element atparallel offset and opposite side walls of the frame structure and liftthe edge sections and move them proximal to two congruent seal surfacestructures at the pressure valve in the upper forming tool half, whereinthe entire hot foil element is formed into the monodirectionally formedblank. The configuration of the blank is substantially similar to alongitudinal contour of the trim piece illustrated in FIG. 13A.

Compressed air that is heated to a temperature of approximately 90° C.to 100° C. is introduced into the pressure valve under a pressure of 90bar. This air pressure is maintained for approximately 3 seconds.Subsequently ventilation is performed for approximately 4 to 8 seconds.Thereafter the upper forming tool half is lifted by approximately 80 mmin another time period of 15 to 20 seconds. Through a lowering of thelower forming tool half also the pallet frame with the 3D-formed elementplaced thereon is lowered to the transport frame that is held in placeon the rails and the transport frame is moved into the loading andunloading station. There, the 3D-formed element is removed by hand andis ready for further processing.

During the further processing the 3D-form element produced according tothe invention is inserted into an injecting mold and back injected withanother synthetic material that melts into liquid form, thusadvantageously with PC/ABS material.

Trying to form that same 3D-form element according to the conventionalHPF method in one step from the flat laminate directly into the 3D-formelement would require at least a rectangular, flat foil element with alength of 1500 mm and a width of 500 mm in order to provide pull surfacethat are required for expanding and stretching the foil material. The3D-formed element would have a high level of internal tensions and layerthickness variations.

Embodiment 2

An essentially rectangular rear window for a medium-sized car shall beprovided. A window length transversal to the vehicle driving directionis greater than a window width. The window width is defined by twostraight slightly outward slanted width edges so that an upper windowlength (adjacent to the vehicle roof) is 1080 mm and a lower windowlength between the lower width edge ends is 1200 mm. The upperlongitudinal side edge is slightly concave with respect to a cord thatconnects the two upper width side edges with one another at a distancefrom 40 mm at the central depression from the cord. The lowerlongitudinal side edge is highly convex and rounded with respect to acord that connects the two lower width side edge ends with each other ata distance of 300 mm from the center apex to the cord. The window widthbetween the center valley at the upper longitudinal side edge and theape at the lower longitudinal side edge is 830 mm. The rear window has acamber wherein the longitudinal contour is configured more cambered thanthe width contour.

A rear window pane of this type is produced from a two-layer coextrudedplate which is made from a 3 mm thick PC-layer and a 2 mm thickPMMA-layer. During production a PMMA-layer is extruded onto a hot, justextruded PC-layer and both layers are run through a calender roller gap.A flat plate with dimensions of 900 mm×1300 mm is cut from the cooledweb. The PMMA-layer later forms the outer layer of the rear window paneat this plate. The PC-layer at the rear window pane is oriented towardsan interior of the vehicle. At the flat plate a band made from blackpaint is printed onto the PC layer by silk screening wherein the band isadapted to a circumferential contour of the rear window pane. The bandhas a width of 100 mm adjacent to the upper longitudinal side edge. Atthe remaining edges a band width of 70 mm is provided. At an inner edgeof the band a number and density of black dots applied by silk screeningdecreases in order to provide a sliding transition to an inner surfaceof the rear window pane that has no print. On this inner surface linesmade from metal particle paste are printed which form conductive pathsfor heating wires. Subsequently a respectively UV-hardening hard coatlayer is applied to the PC-layer and to the PMMA-layer. Thus a liquidproduct can be sprayed on which is sold by Nanogate Glazing SystemsB.V., NL-5667 KZ Geldrup, The Netherlands, under the tradename SICRALAN®hardcoat coating (SICRALAN® is a registered trademark).

Upon the flat plate thus prepared the two stage forming according to theinvention is performed. This plate has a form surface of 1250 mm×850 mmwithin its edge zone. The two-stage forming is performed in a machinedeveloped and built by NIEBLING GMBH 82377 Penzberg, Germany, which isconfigured and equipped according to FIG. 7. The forming tool isconfigured essentially according to FIGS. 8 and 9 and configured for aform surface of 1250 mm×850 mm.

The heating station has two heat screens that have identical surfaceareas and that are equipped with infrared flat radiators and arranged ata distance of 250 mm from each other. Each heat screen surface is largerthan the plate surface. Both heat screens are maintained at atemperature of 360 degrees C. The plate with ambient temperature isplaced on the pallet frame which rests on the transport frame so thatthe plate is centrally arranged between both heating screens and heatedwithin approximately 180 seconds to a surface temperature of 160 degreesC. After reaching the forming temperature the hot plate is run back intothe forming station within 2 seconds and arranged there inside theforming tool that is in its release position. The lower forming toolhalf is raised and reaches its closing position in approximately 1second, wherein the lower form table raises the spring frame and theframe super structure arranged thereon, wherein the two non-flat contactsurface contours reach under two edge sections at the longitudinal sidesof the hot plate that are parallel, offset and opposite to each other atparallel, offset and opposite side walls of the frame superstructure sothat the hot plate is raised and moved proximal to two congruent ceilingsurface contours at the pressure valve in the upper forming tool half,wherein the entire hot plate is formed I a time period of 2 to 3 secondsinto the monodirectionally formed blank. This configuration of the blankis substantially adapted to the long contour of the rear window pane tobe produced and has an apex height of approximately 120 mm at the convexapex relative to the offset flat plate sections.

Compressed air with a pressure of 90 bar that is heated to a temperatureof approximately 90° C. to 100° C. is introduced in the pressure valve.This air press is maintained for approximately 5 seconds, thereafter aventilation is performed within a time period of 4 to 8 seconds.Thereafter the upper forming tool half is raised by approximately 150 mmwithin an additional time period of 30 to 50 seconds. Lowering the lowerforming tool half also lowers the pallet frame with the 3D-formedelement resting thereon onto the transport frame that is held in placeat the rails and the transport frame is run into the loading andunloading station. When moving out of the open forming tool the rearwindow pane blank has a temperature of approximately 60° C. In theloading and unloading station the rear window pane blank is removed byhand and processed further.

During further processing UV-hardening of the coating at the top side(rear window pane outside) is performed and a UV-hardening of thecoating at the bottom side cooled rear window blank (rear window paneinside) is performed. After this UV-hardening the blank is cut to sizeby a 3D-milling machine to match the final dimensions and acircumferential contour of the rear window pane. The edges that areformed are deburred and finished. Furthermore, an electrical connectionis applied to contact the heating wires.

1-19. (canceled) 20: A forming tool for high pressure forming a singlelayer or multi-layer laminate element, the forming tool comprising: anupper forming tool half which forms a pressure bell into which a fluidpressure medium, in particular compressed air is introducible at a fluidmedium pressure of 20 bar to 300 bar, and which includes acircumferential sealing surface in which a circumferential groove isrecessed into which a sealing device is inserted; and a lower formingtool half, which includes a base plate on which a substructure issupported at which a form with form contours or a carrier element thatis to be laminated and which is provided with 3-D carrier elementcontours is attached, at which contours the laminate that is loaded withthe fluid pressure medium is formed, and wherein the substructure isenveloped by a tension frame supported at the base plate or by a springframe that is supported on compression springs (58) at the base platewherein the hot laminate element to be formed is applicable to thetension frame or the spring frame; and wherein the lower forming toolhalf is able to assume a release position that is remote from the upperforming tool half and a closing position that is adjacent to the upperforming tool half, wherein in this release position the transport framewith the frame shaped pallet and the hot laminate element placed thereonis insertable between the two forming tool halves and assumes a positionin which the tension spring or the spring frame and assumes anarrangement within and below the recess at the frame shaped pallet,wherein in the closing position the hot laminate element maintains asmall distance from the sealing surface at the pressure bell and isapplicable at this location to the sealing device so that the pressurebell is sealed pressure tight relative to the laminate element, andwherein in this arrangement a fluid pressure medium is introducible at apressure medium pressure of 20 bar to 300 bar which forms the hotlaminate element within a time period of less than 5 secondsisostatically to the form contours or to the 3-D carrier elementcontours, wherein the tension frame of the spring frame includes arespective contact surface section including a non-flat contour at twoparallel offset and opposite frame sections wherein the respectivecontact surface sections form a non-flat contact surface in combination,or wherein the tension frame or the spring frame includes a frame onwhich a frame assembly is supported and fixed which includes arespective contact surface section including a non-flat contour at twoside walls that are parallel offset from each other and arrangedopposite to each other wherein both contact surface sections form anon-flat contact surface contour, wherein the pressure bell respectivelyincludes a sealing surface section at pressure bell sections that arearranged in parallel with an offset from each other and opposite to eachother wherein the respective sealing surface sections include a non-flatcontour which form a non-flat sealing surface contour in combination,wherein the non-flat sealing surface contour is configured congruent tothe non-flat contact surface contour; and wherein during lifting of thelower forming tool half for reaching the closing position of the formingtool the non-flat contact surface sections reach under two paralleloffset and opposing laminate element rim sections at the tension frame,the spring frame or the frame assembly and the non-flat contact surfacesections move the laminate element rim sections along and eventuallyproximal to the sealing surface including the non-flat sealing surfacecontour of the pressure bell so that the entire hot flat laminateelement is formed at the congruent non-flat contours monoaxial along anaxis orthogonal to the laminate plane and only in the first laminatematerial direction thus mono directionally into a blank that is adaptedto the contours and formed mono directionally. 21: The forming toolaccording to claim 20, wherein the non-flat contours arranged at thecontact surface of the tension frame or the spring frame or at thesidewalls of the frame assembly are cambered roof shaped evenly orunevenly and respectively provided with an apex point or configured waveshaped or ascending with several steps or include other curvedboundaries. 22: The forming tool according to claim 20, wherein duringthe lifting movement of lower forming tool half the frame of the tensionframe or of the spring frame reaches under a bottom side of the frameshaped pallet at an inner circumference of the pallet with a rim zone ofthe frame, lifts the pallet with the laminate arranged thereon for acertain distance and thus disengages and separates the laminate from thetransport frame that is fixed in place. 23: The forming tool accordingto claim 20, wherein a spring frame is provided that is supported at thebase plate by compression springs wherein the spring frame includes aframe at which a frame assembly is supported and attached whose sidewalls provide the non-flat contact surface sections for forming the hotflat laminate element into the mono directionally formed blank, whereinthe spring frame reaches an upper dead center after forming the hot flatlaminate element into the mono directionally formed blank; subsequentlythe lifting movement of the lower forming tool half is continued whereinthe compression springs are compressed without further lifting thespring frame, and wherein the form with the mold contours or the 3-Dcarrier element with its 3-D carrier element contours penetrates atleast partially through a shape of the hot blank during a continuationof the lifting movement and causes an orienting mechanical positiveforming at the blank. 24: The forming tool according to claim 20,wherein the sealing device at the sealing surface of the pressure bellis a strand shaped profile seal which includes a body that is insertedinto a groove at a sealing surface, wherein an elastic seal lipprotrudes from the body which seal lip includes an outer seal lip flankand an inner seal lip flank, wherein in a closing position of theforming tool the contact surface maintains a distance at the lowerforming tool half from the seal surface at the upper forming tool half,wherein the distance has a dimension: [thickness of the laminate elementto be formed plus (100 μm to 1200 μm)] so that a gap between thenon-flat contact surface and the non-flat seal surface is formed, andwherein the pressure fluid flowing under a high pressure fluid pressureinto the pressure bell impacts an inner seal lip flank and deforms theelastic seal lip so that the seal lip bridges a gap and seals the rimzone at the mono directionally formed blank pressure tight relative tothe seal surface at the pressure bell. 25: The forming tool according toclaim 20, wherein after completion of isostatic high pressure formingand ventilating the pressure bell the frame shaped pallet on which theformed element or the laminated 3-D carrier element is arranged is lowerable relative to the upper forming tool half and place able onto thetransport frame that is fixed in place, and wherein thereafter the upperforming tool half is liftable by a predetermined amount in order torender the transport frame with the 3-D formed element placed thereon orthe coated 3-D carrier element removable without interference from theforming zone and movable into the loading and unloading station. 26: Theforming tool according to claim 20, wherein the flat laminate element tobe formed is placeable on a flat frame shaped pallet whose frame isprovided at its inner circumference with a number of offset inwardextending protrusions and the rim zone (6) of the laminate element isonly placed onto the protrusions. 27: The forming tool according toclaim 26, wherein the tension frame or the spring frame or the sidesurfaces of the frame assembly supported and fixed on the frame of thespring frame include a structured outer circumference and a non-flatcontact surface with inward extending recesses and outward extendingbars at the outer circumference, wherein the outer circumference isadapted to the inner circumference at the frame of the frame shapedpallet so that the clamping frame or the spring frame or the frameassembly is movable at a closed distance from the inner circumference ofthe pallet frame relative to the pallet that is fixed in place, whereinthe protrusions at the inner circumference of the pallet frame engagerecesses at the outer circumference of the tension frame or of thespring frame or of the frame assembly, wherein the protruding bars atthe outer circumference at the tension frame or the spring frame or theframe assembly engage the intermediary spaces between two respectiveadjacent protrusions at the pallet frame, wherein when lifting thetension frame or the spring frame or the frame assembly relative to thepallet that is fixed in place the protruding bars at the outercircumference of the tension frame or the spring frame or the frameassembly reach below the rim sections of the flat laminate element andmove them along so that they deposit the laminate element on the contactsurface at the tension frame or at the spring frame or at the frameassembly, so that during an additional lifting of the tension frame orof the spring frame or of the frame shaped super structure with respectto the fixated upper forming tool half the laminate element is formedmono directionally into a mono directionally formed blank between thenon-flat contact surface contour and the congruent non-flat sealingsurface contour. 28: The forming tool according the claim 27, whereinvertically protruding mandrels are attached at selected protrusions atan inner circumference of the pallet frame wherein the mandrels engagebore holes or slotted holes that are recessed in the rim zone of thelaminate element so that portions of the rim zones can slide on theframe of the frame shaped pallet.